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LibTactics.html
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<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8"/>
<link href="coqdoc.css" rel="stylesheet" type="text/css"/>
<title>LibTactics: A Collection of Handy General-Purpose Tactics</title>
<script type="text/javascript" src="jquery-1.8.3.js"></script>
<script type="text/javascript" src="main.js"></script>
</head>
<body>
<div id="page">
<div id="header">
</div>
<div id="main">
<h1 class="libtitle">LibTactics<span class="subtitle">A Collection of Handy General-Purpose Tactics</span></h1>
<div class="code code-tight">
</div>
<div class="doc">
</div>
<div class="code code-tight">
<br/>
<span class="comment">(* $Date: 2013-01-16 22:29:57 -0500 (Wed, 16 Jan 2013) $ *)</span><br/>
<span class="comment">(* Chapter maintained by Arthur Chargueraud *)</span><br/>
<br/>
</div>
<div class="doc">
This file contains a set of tactics that extends the set of builtin
tactics provided with the standard distribution of Coq. It intends
to overcome a number of limitations of the standard set of tactics,
and thereby to help user to write shorter and more robust scripts.
<div class="paragraph"> </div>
Hopefully, Coq tactics will be improved as time goes by, and this
file should ultimately be useless. In the meanwhile, serious Coq
users will probably find it very useful.
<div class="paragraph"> </div>
The present file contains the implementation and the detailed
documentation of those tactics. The SF reader need not read this
file; instead, he/she is encouraged to read the chapter named
UseTactics.v, which is gentle introduction to the most useful
tactics from the LibTactic library.
<div class="paragraph"> </div>
The main features offered are:
<div class="paragraph"> </div>
<ul class="doclist">
<li> More convenient syntax for naming hypotheses, with tactics for
introduction and inversion that take as input only the name of
hypotheses of type <span class="inlinecode"><span class="id" type="keyword">Prop</span></span>, rather than the name of all variables.
</li>
<li> Tactics providing true support for manipulating N-ary conjunctions,
disjunctions and existentials, hidding the fact that the underlying
implementation is based on binary predicates.
</li>
<li> Convenient support for automation: tactic followed with the symbol
"~" or "*" will call automation on the generated subgoals.
Symbol "~" stands for <span class="inlinecode"><span class="id" type="tactic">auto</span></span> and "*" for <span class="inlinecode"><span class="id" type="tactic">intuition</span></span> <span class="inlinecode"><span class="id" type="tactic">eauto</span></span>.
These bindings can be customized.
</li>
<li> Forward-chaining tactics are provided to instantiate lemmas
either with variable or hypotheses or a mix of both.
</li>
<li> A more powerful implementation of <span class="inlinecode"><span class="id" type="tactic">apply</span></span> is provided (it is based
on <span class="inlinecode"><span class="id" type="tactic">refine</span></span> and thus behaves better with respect to conversion).
</li>
<li> An improved inversion tactic which substitutes equalities on variables
generated by the standard inversion mecanism. Moreover, it supports
the elimination of dependently-typed equalities (requires axiom <span class="inlinecode"><span class="id" type="var">K</span></span>,
which is a weak form of Proof Irrelevance).
</li>
<li> Tactics for saving time when writing proofs, with tactics to
asserts hypotheses or sub-goals, and improved tactics for
clearing, renaming, and sorting hypotheses.
</li>
</ul>
<div class="paragraph"> </div>
External credits:
<div class="paragraph"> </div>
<ul class="doclist">
<li> thanks to Xavier Leroy for providing the idea of tactic <span class="inlinecode"><span class="id" type="var">forward</span></span>,
</li>
<li> thanks to Georges Gonthier for the implementation trick in <span class="inlinecode"><span class="id" type="var">rapply</span></span>,
</li>
</ul>
</div>
<div class="code code-tight">
<br/>
<span class="id" type="keyword">Set</span> <span class="id" type="keyword">Implicit</span> <span class="id" type="var">Arguments</span>.<br/>
<br/>
<span class="comment">(* ********************************************************************** *)</span><br/>
</div>
<div class="doc">
<a name="lab906"></a><h1 class="section">Additional notations for Coq</h1>
</div>
<div class="code code-space">
<br/>
<span class="comment">(* ---------------------------------------------------------------------- *)</span><br/>
</div>
<div class="doc">
<a name="lab907"></a><h2 class="section">N-ary Existentials</h2>
<div class="paragraph"> </div>
<span class="inlinecode"><span style="font-family: arial;">∃</span></span> <span class="inlinecode"><span class="id" type="var">T<sub>1</sub></span></span> <span class="inlinecode">...</span> <span class="inlinecode"><span class="id" type="var">TN</span>,</span> <span class="inlinecode"><span class="id" type="var">P</span></span> is a shorthand for
<span class="inlinecode"><span style="font-family: arial;">∃</span></span> <span class="inlinecode"><span class="id" type="var">T<sub>1</sub></span>,</span> <span class="inlinecode">...,</span> <span class="inlinecode"><span style="font-family: arial;">∃</span></span> <span class="inlinecode"><span class="id" type="var">TN</span>,</span> <span class="inlinecode"><span class="id" type="var">P</span></span>. Note that
<span class="inlinecode"><span class="id" type="var">Coq.Program.Syntax</span></span> already defines exists
for arity up to 4.
</div>
<div class="code code-tight">
<br/>
<span class="id" type="keyword">Notation</span> "'exists' x1 ',' P" :=<br/>
(<span style="font-family: arial;">∃</span><span class="id" type="var">x1</span>, <span class="id" type="var">P</span>)<br/>
(<span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 200, <span class="id" type="var">x1</span> <span class="id" type="var">ident</span>, <br/>
<span class="id" type="var">right</span> <span class="id" type="var">associativity</span>) : <span class="id" type="var">type_scope</span>.<br/>
<span class="id" type="keyword">Notation</span> "'exists' x1 x2 ',' P" :=<br/>
(<span style="font-family: arial;">∃</span><span class="id" type="var">x1</span>, <span style="font-family: arial;">∃</span><span class="id" type="var">x2</span>, <span class="id" type="var">P</span>)<br/>
(<span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 200, <span class="id" type="var">x1</span> <span class="id" type="var">ident</span>, <span class="id" type="var">x2</span> <span class="id" type="var">ident</span>, <br/>
<span class="id" type="var">right</span> <span class="id" type="var">associativity</span>) : <span class="id" type="var">type_scope</span>.<br/>
<span class="id" type="keyword">Notation</span> "'exists' x1 x2 x3 ',' P" :=<br/>
(<span style="font-family: arial;">∃</span><span class="id" type="var">x1</span>, <span style="font-family: arial;">∃</span><span class="id" type="var">x2</span>, <span style="font-family: arial;">∃</span><span class="id" type="var">x3</span>, <span class="id" type="var">P</span>)<br/>
(<span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 200, <span class="id" type="var">x1</span> <span class="id" type="var">ident</span>, <span class="id" type="var">x2</span> <span class="id" type="var">ident</span>, <span class="id" type="var">x3</span> <span class="id" type="var">ident</span>, <br/>
<span class="id" type="var">right</span> <span class="id" type="var">associativity</span>) : <span class="id" type="var">type_scope</span>.<br/>
<span class="id" type="keyword">Notation</span> "'exists' x1 x2 x3 x4 ',' P" :=<br/>
(<span style="font-family: arial;">∃</span><span class="id" type="var">x1</span>, <span style="font-family: arial;">∃</span><span class="id" type="var">x2</span>, <span style="font-family: arial;">∃</span><span class="id" type="var">x3</span>, <span style="font-family: arial;">∃</span><span class="id" type="var">x4</span>, <span class="id" type="var">P</span>)<br/>
(<span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 200, <span class="id" type="var">x1</span> <span class="id" type="var">ident</span>, <span class="id" type="var">x2</span> <span class="id" type="var">ident</span>, <span class="id" type="var">x3</span> <span class="id" type="var">ident</span>, <span class="id" type="var">x4</span> <span class="id" type="var">ident</span>, <br/>
<span class="id" type="var">right</span> <span class="id" type="var">associativity</span>) : <span class="id" type="var">type_scope</span>.<br/>
<span class="id" type="keyword">Notation</span> "'exists' x1 x2 x3 x4 x5 ',' P" :=<br/>
(<span style="font-family: arial;">∃</span><span class="id" type="var">x1</span>, <span style="font-family: arial;">∃</span><span class="id" type="var">x2</span>, <span style="font-family: arial;">∃</span><span class="id" type="var">x3</span>, <span style="font-family: arial;">∃</span><span class="id" type="var">x4</span>, <span style="font-family: arial;">∃</span><span class="id" type="var">x5</span>, <span class="id" type="var">P</span>)<br/>
(<span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 200, <span class="id" type="var">x1</span> <span class="id" type="var">ident</span>, <span class="id" type="var">x2</span> <span class="id" type="var">ident</span>, <span class="id" type="var">x3</span> <span class="id" type="var">ident</span>, <span class="id" type="var">x4</span> <span class="id" type="var">ident</span>, <span class="id" type="var">x5</span> <span class="id" type="var">ident</span>,<br/>
<span class="id" type="var">right</span> <span class="id" type="var">associativity</span>) : <span class="id" type="var">type_scope</span>.<br/>
<span class="id" type="keyword">Notation</span> "'exists' x1 x2 x3 x4 x5 x6 ',' P" :=<br/>
(<span style="font-family: arial;">∃</span><span class="id" type="var">x1</span>, <span style="font-family: arial;">∃</span><span class="id" type="var">x2</span>, <span style="font-family: arial;">∃</span><span class="id" type="var">x3</span>, <span style="font-family: arial;">∃</span><span class="id" type="var">x4</span>, <span style="font-family: arial;">∃</span><span class="id" type="var">x5</span>, <span style="font-family: arial;">∃</span><span class="id" type="var">x6</span>, <span class="id" type="var">P</span>)<br/>
(<span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 200, <span class="id" type="var">x1</span> <span class="id" type="var">ident</span>, <span class="id" type="var">x2</span> <span class="id" type="var">ident</span>, <span class="id" type="var">x3</span> <span class="id" type="var">ident</span>, <span class="id" type="var">x4</span> <span class="id" type="var">ident</span>, <span class="id" type="var">x5</span> <span class="id" type="var">ident</span>,<br/>
<span class="id" type="var">x6</span> <span class="id" type="var">ident</span>,<br/>
<span class="id" type="var">right</span> <span class="id" type="var">associativity</span>) : <span class="id" type="var">type_scope</span>.<br/>
<span class="id" type="keyword">Notation</span> "'exists' x1 x2 x3 x4 x5 x6 x7 ',' P" :=<br/>
(<span style="font-family: arial;">∃</span><span class="id" type="var">x1</span>, <span style="font-family: arial;">∃</span><span class="id" type="var">x2</span>, <span style="font-family: arial;">∃</span><span class="id" type="var">x3</span>, <span style="font-family: arial;">∃</span><span class="id" type="var">x4</span>, <span style="font-family: arial;">∃</span><span class="id" type="var">x5</span>, <span style="font-family: arial;">∃</span><span class="id" type="var">x6</span>, <br/>
<span style="font-family: arial;">∃</span><span class="id" type="var">x7</span>, <span class="id" type="var">P</span>)<br/>
(<span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 200, <span class="id" type="var">x1</span> <span class="id" type="var">ident</span>, <span class="id" type="var">x2</span> <span class="id" type="var">ident</span>, <span class="id" type="var">x3</span> <span class="id" type="var">ident</span>, <span class="id" type="var">x4</span> <span class="id" type="var">ident</span>, <span class="id" type="var">x5</span> <span class="id" type="var">ident</span>,<br/>
<span class="id" type="var">x6</span> <span class="id" type="var">ident</span>, <span class="id" type="var">x7</span> <span class="id" type="var">ident</span>,<br/>
<span class="id" type="var">right</span> <span class="id" type="var">associativity</span>) : <span class="id" type="var">type_scope</span>.<br/>
<span class="id" type="keyword">Notation</span> "'exists' x1 x2 x3 x4 x5 x6 x7 x8 ',' P" :=<br/>
(<span style="font-family: arial;">∃</span><span class="id" type="var">x1</span>, <span style="font-family: arial;">∃</span><span class="id" type="var">x2</span>, <span style="font-family: arial;">∃</span><span class="id" type="var">x3</span>, <span style="font-family: arial;">∃</span><span class="id" type="var">x4</span>, <span style="font-family: arial;">∃</span><span class="id" type="var">x5</span>, <span style="font-family: arial;">∃</span><span class="id" type="var">x6</span>, <br/>
<span style="font-family: arial;">∃</span><span class="id" type="var">x7</span>, <span style="font-family: arial;">∃</span><span class="id" type="var">x8</span>, <span class="id" type="var">P</span>)<br/>
(<span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 200, <span class="id" type="var">x1</span> <span class="id" type="var">ident</span>, <span class="id" type="var">x2</span> <span class="id" type="var">ident</span>, <span class="id" type="var">x3</span> <span class="id" type="var">ident</span>, <span class="id" type="var">x4</span> <span class="id" type="var">ident</span>, <span class="id" type="var">x5</span> <span class="id" type="var">ident</span>,<br/>
<span class="id" type="var">x6</span> <span class="id" type="var">ident</span>, <span class="id" type="var">x7</span> <span class="id" type="var">ident</span>, <span class="id" type="var">x8</span> <span class="id" type="var">ident</span>,<br/>
<span class="id" type="var">right</span> <span class="id" type="var">associativity</span>) : <span class="id" type="var">type_scope</span>.<br/>
<span class="id" type="keyword">Notation</span> "'exists' x1 x2 x3 x4 x5 x6 x7 x8 x9 ',' P" :=<br/>
(<span style="font-family: arial;">∃</span><span class="id" type="var">x1</span>, <span style="font-family: arial;">∃</span><span class="id" type="var">x2</span>, <span style="font-family: arial;">∃</span><span class="id" type="var">x3</span>, <span style="font-family: arial;">∃</span><span class="id" type="var">x4</span>, <span style="font-family: arial;">∃</span><span class="id" type="var">x5</span>, <span style="font-family: arial;">∃</span><span class="id" type="var">x6</span>, <br/>
<span style="font-family: arial;">∃</span><span class="id" type="var">x7</span>, <span style="font-family: arial;">∃</span><span class="id" type="var">x8</span>, <span style="font-family: arial;">∃</span><span class="id" type="var">x9</span>, <span class="id" type="var">P</span>)<br/>
(<span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 200, <span class="id" type="var">x1</span> <span class="id" type="var">ident</span>, <span class="id" type="var">x2</span> <span class="id" type="var">ident</span>, <span class="id" type="var">x3</span> <span class="id" type="var">ident</span>, <span class="id" type="var">x4</span> <span class="id" type="var">ident</span>, <span class="id" type="var">x5</span> <span class="id" type="var">ident</span>,<br/>
<span class="id" type="var">x6</span> <span class="id" type="var">ident</span>, <span class="id" type="var">x7</span> <span class="id" type="var">ident</span>, <span class="id" type="var">x8</span> <span class="id" type="var">ident</span>, <span class="id" type="var">x9</span> <span class="id" type="var">ident</span>,<br/>
<span class="id" type="var">right</span> <span class="id" type="var">associativity</span>) : <span class="id" type="var">type_scope</span>.<br/>
<span class="id" type="keyword">Notation</span> "'exists' x1 x2 x3 x4 x5 x6 x7 x8 x9 x10 ',' P" :=<br/>
(<span style="font-family: arial;">∃</span><span class="id" type="var">x1</span>, <span style="font-family: arial;">∃</span><span class="id" type="var">x2</span>, <span style="font-family: arial;">∃</span><span class="id" type="var">x3</span>, <span style="font-family: arial;">∃</span><span class="id" type="var">x4</span>, <span style="font-family: arial;">∃</span><span class="id" type="var">x5</span>, <span style="font-family: arial;">∃</span><span class="id" type="var">x6</span>, <br/>
<span style="font-family: arial;">∃</span><span class="id" type="var">x7</span>, <span style="font-family: arial;">∃</span><span class="id" type="var">x8</span>, <span style="font-family: arial;">∃</span><span class="id" type="var">x9</span>, <span style="font-family: arial;">∃</span><span class="id" type="var">x10</span>, <span class="id" type="var">P</span>)<br/>
(<span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 200, <span class="id" type="var">x1</span> <span class="id" type="var">ident</span>, <span class="id" type="var">x2</span> <span class="id" type="var">ident</span>, <span class="id" type="var">x3</span> <span class="id" type="var">ident</span>, <span class="id" type="var">x4</span> <span class="id" type="var">ident</span>, <span class="id" type="var">x5</span> <span class="id" type="var">ident</span>,<br/>
<span class="id" type="var">x6</span> <span class="id" type="var">ident</span>, <span class="id" type="var">x7</span> <span class="id" type="var">ident</span>, <span class="id" type="var">x8</span> <span class="id" type="var">ident</span>, <span class="id" type="var">x9</span> <span class="id" type="var">ident</span>, <span class="id" type="var">x10</span> <span class="id" type="var">ident</span>,<br/>
<span class="id" type="var">right</span> <span class="id" type="var">associativity</span>) : <span class="id" type="var">type_scope</span>.<br/>
<br/>
<span class="comment">(* ********************************************************************** *)</span><br/>
</div>
<div class="doc">
<a name="lab908"></a><h1 class="section">Tools for programming with Ltac</h1>
</div>
<div class="code code-space">
<br/>
<span class="comment">(* ---------------------------------------------------------------------- *)</span><br/>
</div>
<div class="doc">
<a name="lab909"></a><h2 class="section">Identity continuation</h2>
</div>
<div class="code code-space">
<br/>
<span class="id" type="keyword">Ltac</span> <span class="id" type="var">idcont</span> <span class="id" type="var">tt</span> := <br/>
<span class="id" type="var">idtac</span>.<br/>
<br/>
<span class="comment">(* ---------------------------------------------------------------------- *)</span><br/>
</div>
<div class="doc">
<a name="lab910"></a><h2 class="section">Untyped arguments for tactics</h2>
<div class="paragraph"> </div>
Any Coq value can be boxed into the type <span class="inlinecode"><span class="id" type="var">Boxer</span></span>. This is
useful to use Coq computations for implementing tactics.
</div>
<div class="code code-tight">
<br/>
<span class="id" type="keyword">Inductive</span> <span class="id" type="var">Boxer</span> : <span class="id" type="keyword">Type</span> :=<br/>
| <span class="id" type="var">boxer</span> : <span style="font-family: arial;">∀</span>(<span class="id" type="var">A</span>:<span class="id" type="keyword">Type</span>), <span class="id" type="var">A</span> <span style="font-family: arial;">→</span> <span class="id" type="var">Boxer</span>.<br/>
<br/>
<span class="comment">(* ---------------------------------------------------------------------- *)</span><br/>
</div>
<div class="doc">
<a name="lab911"></a><h2 class="section">Optional arguments for tactics</h2>
<div class="paragraph"> </div>
<span class="inlinecode"><span class="id" type="var">ltac_no_arg</span></span> is a constant that can be used to simulate
optional arguments in tactic definitions.
Use <span class="inlinecode"><span class="id" type="var">mytactic</span></span> <span class="inlinecode"><span class="id" type="var">ltac_no_arg</span></span> on the tactic invokation,
and use <span class="inlinecode"><span class="id" type="keyword">match</span></span> <span class="inlinecode"><span class="id" type="var">arg</span></span> <span class="inlinecode"><span class="id" type="keyword">with</span></span> <span class="inlinecode"><span class="id" type="var">ltac_no_arg</span></span> <span class="inlinecode">⇒</span> <span class="inlinecode">..</span> or
<span class="inlinecode"><span class="id" type="keyword">match</span></span> <span class="inlinecode"><span class="id" type="var">type</span></span> <span class="inlinecode"><span class="id" type="var">of</span></span> <span class="inlinecode"><span class="id" type="var">arg</span></span> <span class="inlinecode"><span class="id" type="keyword">with</span></span> <span class="inlinecode"><span class="id" type="var">ltac_No_arg</span></span> <span class="inlinecode">⇒</span> <span class="inlinecode">..</span> to
test whether an argument was provided.
</div>
<div class="code code-tight">
<br/>
<span class="id" type="keyword">Inductive</span> <span class="id" type="var">ltac_No_arg</span> : <span class="id" type="keyword">Set</span> := <br/>
| <span class="id" type="var">ltac_no_arg</span> : <span class="id" type="var">ltac_No_arg</span>.<br/>
<br/>
<span class="comment">(* ---------------------------------------------------------------------- *)</span><br/>
</div>
<div class="doc">
<a name="lab912"></a><h2 class="section">Wildcard arguments for tactics</h2>
<div class="paragraph"> </div>
<span class="inlinecode"><span class="id" type="var">ltac_wild</span></span> is a constant that can be used to simulate
wildcard arguments in tactic definitions. Notation is <span class="inlinecode"><span class="id" type="var">__</span></span>.
</div>
<div class="code code-tight">
<br/>
<span class="id" type="keyword">Inductive</span> <span class="id" type="var">ltac_Wild</span> : <span class="id" type="keyword">Set</span> := <br/>
| <span class="id" type="var">ltac_wild</span> : <span class="id" type="var">ltac_Wild</span>.<br/>
<br/>
<span class="id" type="keyword">Notation</span> "'__'" := <span class="id" type="var">ltac_wild</span> : <span class="id" type="var">ltac_scope</span>.<br/>
<br/>
</div>
<div class="doc">
<span class="inlinecode"><span class="id" type="var">ltac_wilds</span></span> is another constant that is typically used to
simulate a sequence of <span class="inlinecode"><span class="id" type="var">N</span></span> wildcards, with <span class="inlinecode"><span class="id" type="var">N</span></span> chosen
appropriately depending on the context. Notation is <span class="inlinecode"><span class="id" type="var">___</span></span>.
</div>
<div class="code code-tight">
<br/>
<span class="id" type="keyword">Inductive</span> <span class="id" type="var">ltac_Wilds</span> : <span class="id" type="keyword">Set</span> := <br/>
| <span class="id" type="var">ltac_wilds</span> : <span class="id" type="var">ltac_Wilds</span>.<br/>
<br/>
<span class="id" type="keyword">Notation</span> "'___'" := <span class="id" type="var">ltac_wilds</span> : <span class="id" type="var">ltac_scope</span>.<br/>
<br/>
<span class="id" type="keyword">Open</span> <span class="id" type="keyword">Scope</span> <span class="id" type="var">ltac_scope</span>.<br/>
<br/>
<span class="comment">(* ---------------------------------------------------------------------- *)</span><br/>
</div>
<div class="doc">
<a name="lab913"></a><h2 class="section">Position markers</h2>
<div class="paragraph"> </div>
<span class="inlinecode"><span class="id" type="var">ltac_Mark</span></span> and <span class="inlinecode"><span class="id" type="var">ltac_mark</span></span> are dummy definitions used as sentinel
by tactics, to mark a certain position in the context or in the goal.
</div>
<div class="code code-tight">
<br/>
<span class="id" type="keyword">Inductive</span> <span class="id" type="var">ltac_Mark</span> : <span class="id" type="keyword">Type</span> :=<br/>
| <span class="id" type="var">ltac_mark</span> : <span class="id" type="var">ltac_Mark</span>.<br/>
<br/>
</div>
<div class="doc">
<span class="inlinecode"><span class="id" type="var">gen_until_mark</span></span> repeats <span class="inlinecode"><span class="id" type="tactic">generalize</span></span> on hypotheses from the
context, starting from the bottom and stopping as soon as reaching
an hypothesis of type <span class="inlinecode"><span class="id" type="var">Mark</span></span>. If fails if <span class="inlinecode"><span class="id" type="var">Mark</span></span> does not
appear in the context.
</div>
<div class="code code-tight">
<br/>
<span class="id" type="keyword">Ltac</span> <span class="id" type="var">gen_until_mark</span> :=<br/>
<span class="id" type="keyword">match</span> <span class="id" type="var">goal</span> <span class="id" type="keyword">with</span> <span class="id" type="var">H</span>: ?<span class="id" type="var">T</span> <span style="font-family: arial;">⊢</span> <span class="id" type="var">_</span> ⇒<br/>
<span class="id" type="keyword">match</span> <span class="id" type="var">T</span> <span class="id" type="keyword">with</span> <br/>
| <span class="id" type="var">ltac_Mark</span> ⇒ <span class="id" type="tactic">clear</span> <span class="id" type="var">H</span><br/>
| <span class="id" type="var">_</span> ⇒ <span class="id" type="tactic">generalize</span> <span class="id" type="var">H</span>; <span class="id" type="tactic">clear</span> <span class="id" type="var">H</span>; <span class="id" type="var">gen_until_mark</span><br/>
<span class="id" type="keyword">end</span> <span class="id" type="keyword">end</span>.<br/>
<br/>
</div>
<div class="doc">
<span class="inlinecode"><span class="id" type="var">intro_until_mark</span></span> repeats <span class="inlinecode"><span class="id" type="tactic">intro</span></span> until reaching an hypothesis of
type <span class="inlinecode"><span class="id" type="var">Mark</span></span>. It throws away the hypothesis <span class="inlinecode"><span class="id" type="var">Mark</span></span>.
It fails if <span class="inlinecode"><span class="id" type="var">Mark</span></span> does not appear as an hypothesis in the
goal.
</div>
<div class="code code-tight">
<br/>
<span class="id" type="keyword">Ltac</span> <span class="id" type="var">intro_until_mark</span> :=<br/>
<span class="id" type="keyword">match</span> <span class="id" type="var">goal</span> <span class="id" type="keyword">with</span> <br/>
| <span style="font-family: arial;">⊢</span> (<span class="id" type="var">ltac_Mark</span> <span style="font-family: arial;">→</span> <span class="id" type="var">_</span>) ⇒ <span class="id" type="tactic">intros</span> <span class="id" type="var">_</span><br/>
| <span class="id" type="var">_</span> ⇒ <span class="id" type="tactic">intro</span>; <span class="id" type="var">intro_until_mark</span><br/>
<span class="id" type="keyword">end</span>.<br/>
<br/>
<span class="comment">(* ---------------------------------------------------------------------- *)</span><br/>
</div>
<div class="doc">
<a name="lab914"></a><h2 class="section">List of arguments for tactics</h2>
<div class="paragraph"> </div>
A datatype of type <span class="inlinecode"><span class="id" type="var">list</span></span> <span class="inlinecode"><span class="id" type="var">Boxer</span></span> is used to manipulate list of
Coq values in ltac. Notation is <span class="inlinecode">>></span> <span class="inlinecode"><span class="id" type="var">v<sub>1</sub></span></span> <span class="inlinecode"><span class="id" type="var">v<sub>2</sub></span></span> <span class="inlinecode">...</span> <span class="inlinecode"><span class="id" type="var">vN</span></span> for building
a list containing the values <span class="inlinecode"><span class="id" type="var">v<sub>1</sub></span></span> through <span class="inlinecode"><span class="id" type="var">vN</span></span>.
</div>
<div class="code code-tight">
<br/>
<span class="id" type="keyword">Require</span> <span class="id" type="keyword">Import</span> <span class="id" type="var">List</span>.<br/>
<br/>
<span class="id" type="keyword">Notation</span> "'>>'" :=<br/>
(@<span class="id" type="var">nil</span> <span class="id" type="var">Boxer</span>)<br/>
(<span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0)<br/>
: <span class="id" type="var">ltac_scope</span>.<br/>
<span class="id" type="keyword">Notation</span> "'>>' v<sub>1</sub>" :=<br/>
((<span class="id" type="var">boxer</span> <span class="id" type="var">v<sub>1</sub></span>)::<span class="id" type="var">nil</span>)<br/>
(<span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0, <span class="id" type="var">v<sub>1</sub></span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0)<br/>
: <span class="id" type="var">ltac_scope</span>.<br/>
<span class="id" type="keyword">Notation</span> "'>>' v<sub>1</sub> v<sub>2</sub>" :=<br/>
((<span class="id" type="var">boxer</span> <span class="id" type="var">v<sub>1</sub></span>)::(<span class="id" type="var">boxer</span> <span class="id" type="var">v<sub>2</sub></span>)::<span class="id" type="var">nil</span>)<br/>
(<span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0, <span class="id" type="var">v<sub>1</sub></span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0, <span class="id" type="var">v<sub>2</sub></span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0)<br/>
: <span class="id" type="var">ltac_scope</span>.<br/>
<span class="id" type="keyword">Notation</span> "'>>' v<sub>1</sub> v<sub>2</sub> v<sub>3</sub>" :=<br/>
((<span class="id" type="var">boxer</span> <span class="id" type="var">v<sub>1</sub></span>)::(<span class="id" type="var">boxer</span> <span class="id" type="var">v<sub>2</sub></span>)::(<span class="id" type="var">boxer</span> <span class="id" type="var">v<sub>3</sub></span>)::<span class="id" type="var">nil</span>)<br/>
(<span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0, <span class="id" type="var">v<sub>1</sub></span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0, <span class="id" type="var">v<sub>2</sub></span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0, <span class="id" type="var">v<sub>3</sub></span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0)<br/>
: <span class="id" type="var">ltac_scope</span>.<br/>
<span class="id" type="keyword">Notation</span> "'>>' v<sub>1</sub> v<sub>2</sub> v<sub>3</sub> v4" :=<br/>
((<span class="id" type="var">boxer</span> <span class="id" type="var">v<sub>1</sub></span>)::(<span class="id" type="var">boxer</span> <span class="id" type="var">v<sub>2</sub></span>)::(<span class="id" type="var">boxer</span> <span class="id" type="var">v<sub>3</sub></span>)::(<span class="id" type="var">boxer</span> <span class="id" type="var">v4</span>)::<span class="id" type="var">nil</span>)<br/>
(<span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0, <span class="id" type="var">v<sub>1</sub></span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0, <span class="id" type="var">v<sub>2</sub></span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0, <span class="id" type="var">v<sub>3</sub></span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0,<br/>
<span class="id" type="var">v4</span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0)<br/>
: <span class="id" type="var">ltac_scope</span>.<br/>
<span class="id" type="keyword">Notation</span> "'>>' v<sub>1</sub> v<sub>2</sub> v<sub>3</sub> v4 v5" :=<br/>
((<span class="id" type="var">boxer</span> <span class="id" type="var">v<sub>1</sub></span>)::(<span class="id" type="var">boxer</span> <span class="id" type="var">v<sub>2</sub></span>)::(<span class="id" type="var">boxer</span> <span class="id" type="var">v<sub>3</sub></span>)::(<span class="id" type="var">boxer</span> <span class="id" type="var">v4</span>)::(<span class="id" type="var">boxer</span> <span class="id" type="var">v5</span>)::<span class="id" type="var">nil</span>)<br/>
(<span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0, <span class="id" type="var">v<sub>1</sub></span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0, <span class="id" type="var">v<sub>2</sub></span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0, <span class="id" type="var">v<sub>3</sub></span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0,<br/>
<span class="id" type="var">v4</span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0, <span class="id" type="var">v5</span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0)<br/>
: <span class="id" type="var">ltac_scope</span>.<br/>
<span class="id" type="keyword">Notation</span> "'>>' v<sub>1</sub> v<sub>2</sub> v<sub>3</sub> v4 v5 v6" :=<br/>
((<span class="id" type="var">boxer</span> <span class="id" type="var">v<sub>1</sub></span>)::(<span class="id" type="var">boxer</span> <span class="id" type="var">v<sub>2</sub></span>)::(<span class="id" type="var">boxer</span> <span class="id" type="var">v<sub>3</sub></span>)::(<span class="id" type="var">boxer</span> <span class="id" type="var">v4</span>)::(<span class="id" type="var">boxer</span> <span class="id" type="var">v5</span>)<br/>
::(<span class="id" type="var">boxer</span> <span class="id" type="var">v6</span>)::<span class="id" type="var">nil</span>)<br/>
(<span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0, <span class="id" type="var">v<sub>1</sub></span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0, <span class="id" type="var">v<sub>2</sub></span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0, <span class="id" type="var">v<sub>3</sub></span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0,<br/>
<span class="id" type="var">v4</span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0, <span class="id" type="var">v5</span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0, <span class="id" type="var">v6</span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0)<br/>
: <span class="id" type="var">ltac_scope</span>.<br/>
<span class="id" type="keyword">Notation</span> "'>>' v<sub>1</sub> v<sub>2</sub> v<sub>3</sub> v4 v5 v6 v7" :=<br/>
((<span class="id" type="var">boxer</span> <span class="id" type="var">v<sub>1</sub></span>)::(<span class="id" type="var">boxer</span> <span class="id" type="var">v<sub>2</sub></span>)::(<span class="id" type="var">boxer</span> <span class="id" type="var">v<sub>3</sub></span>)::(<span class="id" type="var">boxer</span> <span class="id" type="var">v4</span>)::(<span class="id" type="var">boxer</span> <span class="id" type="var">v5</span>)<br/>
::(<span class="id" type="var">boxer</span> <span class="id" type="var">v6</span>)::(<span class="id" type="var">boxer</span> <span class="id" type="var">v7</span>)::<span class="id" type="var">nil</span>)<br/>
(<span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0, <span class="id" type="var">v<sub>1</sub></span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0, <span class="id" type="var">v<sub>2</sub></span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0, <span class="id" type="var">v<sub>3</sub></span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0,<br/>
<span class="id" type="var">v4</span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0, <span class="id" type="var">v5</span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0, <span class="id" type="var">v6</span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0, <span class="id" type="var">v7</span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0)<br/>
: <span class="id" type="var">ltac_scope</span>.<br/>
<span class="id" type="keyword">Notation</span> "'>>' v<sub>1</sub> v<sub>2</sub> v<sub>3</sub> v4 v5 v6 v7 v8" :=<br/>
((<span class="id" type="var">boxer</span> <span class="id" type="var">v<sub>1</sub></span>)::(<span class="id" type="var">boxer</span> <span class="id" type="var">v<sub>2</sub></span>)::(<span class="id" type="var">boxer</span> <span class="id" type="var">v<sub>3</sub></span>)::(<span class="id" type="var">boxer</span> <span class="id" type="var">v4</span>)::(<span class="id" type="var">boxer</span> <span class="id" type="var">v5</span>)<br/>
::(<span class="id" type="var">boxer</span> <span class="id" type="var">v6</span>)::(<span class="id" type="var">boxer</span> <span class="id" type="var">v7</span>)::(<span class="id" type="var">boxer</span> <span class="id" type="var">v8</span>)::<span class="id" type="var">nil</span>)<br/>
(<span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0, <span class="id" type="var">v<sub>1</sub></span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0, <span class="id" type="var">v<sub>2</sub></span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0, <span class="id" type="var">v<sub>3</sub></span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0,<br/>
<span class="id" type="var">v4</span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0, <span class="id" type="var">v5</span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0, <span class="id" type="var">v6</span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0, <span class="id" type="var">v7</span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0,<br/>
<span class="id" type="var">v8</span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0)<br/>
: <span class="id" type="var">ltac_scope</span>.<br/>
<span class="id" type="keyword">Notation</span> "'>>' v<sub>1</sub> v<sub>2</sub> v<sub>3</sub> v4 v5 v6 v7 v8 v9" :=<br/>
((<span class="id" type="var">boxer</span> <span class="id" type="var">v<sub>1</sub></span>)::(<span class="id" type="var">boxer</span> <span class="id" type="var">v<sub>2</sub></span>)::(<span class="id" type="var">boxer</span> <span class="id" type="var">v<sub>3</sub></span>)::(<span class="id" type="var">boxer</span> <span class="id" type="var">v4</span>)::(<span class="id" type="var">boxer</span> <span class="id" type="var">v5</span>)<br/>
::(<span class="id" type="var">boxer</span> <span class="id" type="var">v6</span>)::(<span class="id" type="var">boxer</span> <span class="id" type="var">v7</span>)::(<span class="id" type="var">boxer</span> <span class="id" type="var">v8</span>)::(<span class="id" type="var">boxer</span> <span class="id" type="var">v9</span>)::<span class="id" type="var">nil</span>)<br/>
(<span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0, <span class="id" type="var">v<sub>1</sub></span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0, <span class="id" type="var">v<sub>2</sub></span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0, <span class="id" type="var">v<sub>3</sub></span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0,<br/>
<span class="id" type="var">v4</span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0, <span class="id" type="var">v5</span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0, <span class="id" type="var">v6</span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0, <span class="id" type="var">v7</span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0,<br/>
<span class="id" type="var">v8</span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0, <span class="id" type="var">v9</span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0)<br/>
: <span class="id" type="var">ltac_scope</span>.<br/>
<span class="id" type="keyword">Notation</span> "'>>' v<sub>1</sub> v<sub>2</sub> v<sub>3</sub> v4 v5 v6 v7 v8 v9 v10" :=<br/>
((<span class="id" type="var">boxer</span> <span class="id" type="var">v<sub>1</sub></span>)::(<span class="id" type="var">boxer</span> <span class="id" type="var">v<sub>2</sub></span>)::(<span class="id" type="var">boxer</span> <span class="id" type="var">v<sub>3</sub></span>)::(<span class="id" type="var">boxer</span> <span class="id" type="var">v4</span>)::(<span class="id" type="var">boxer</span> <span class="id" type="var">v5</span>)<br/>
::(<span class="id" type="var">boxer</span> <span class="id" type="var">v6</span>)::(<span class="id" type="var">boxer</span> <span class="id" type="var">v7</span>)::(<span class="id" type="var">boxer</span> <span class="id" type="var">v8</span>)::(<span class="id" type="var">boxer</span> <span class="id" type="var">v9</span>)::(<span class="id" type="var">boxer</span> <span class="id" type="var">v10</span>)::<span class="id" type="var">nil</span>)<br/>
(<span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0, <span class="id" type="var">v<sub>1</sub></span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0, <span class="id" type="var">v<sub>2</sub></span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0, <span class="id" type="var">v<sub>3</sub></span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0,<br/>
<span class="id" type="var">v4</span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0, <span class="id" type="var">v5</span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0, <span class="id" type="var">v6</span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0, <span class="id" type="var">v7</span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0,<br/>
<span class="id" type="var">v8</span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0, <span class="id" type="var">v9</span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0, <span class="id" type="var">v10</span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0)<br/>
: <span class="id" type="var">ltac_scope</span>.<br/>
<span class="id" type="keyword">Notation</span> "'>>' v<sub>1</sub> v<sub>2</sub> v<sub>3</sub> v4 v5 v6 v7 v8 v9 v10 v<sub>11</sub>" :=<br/>
((<span class="id" type="var">boxer</span> <span class="id" type="var">v<sub>1</sub></span>)::(<span class="id" type="var">boxer</span> <span class="id" type="var">v<sub>2</sub></span>)::(<span class="id" type="var">boxer</span> <span class="id" type="var">v<sub>3</sub></span>)::(<span class="id" type="var">boxer</span> <span class="id" type="var">v4</span>)::(<span class="id" type="var">boxer</span> <span class="id" type="var">v5</span>)<br/>
::(<span class="id" type="var">boxer</span> <span class="id" type="var">v6</span>)::(<span class="id" type="var">boxer</span> <span class="id" type="var">v7</span>)::(<span class="id" type="var">boxer</span> <span class="id" type="var">v8</span>)::(<span class="id" type="var">boxer</span> <span class="id" type="var">v9</span>)::(<span class="id" type="var">boxer</span> <span class="id" type="var">v10</span>)<br/>
::(<span class="id" type="var">boxer</span> <span class="id" type="var">v<sub>11</sub></span>)::<span class="id" type="var">nil</span>)<br/>
(<span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0, <span class="id" type="var">v<sub>1</sub></span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0, <span class="id" type="var">v<sub>2</sub></span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0, <span class="id" type="var">v<sub>3</sub></span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0,<br/>
<span class="id" type="var">v4</span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0, <span class="id" type="var">v5</span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0, <span class="id" type="var">v6</span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0, <span class="id" type="var">v7</span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0,<br/>
<span class="id" type="var">v8</span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0, <span class="id" type="var">v9</span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0, <span class="id" type="var">v10</span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0, <span class="id" type="var">v<sub>11</sub></span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0)<br/>
: <span class="id" type="var">ltac_scope</span>.<br/>
<span class="id" type="keyword">Notation</span> "'>>' v<sub>1</sub> v<sub>2</sub> v<sub>3</sub> v4 v5 v6 v7 v8 v9 v10 v<sub>11</sub> v<sub>12</sub>" :=<br/>
((<span class="id" type="var">boxer</span> <span class="id" type="var">v<sub>1</sub></span>)::(<span class="id" type="var">boxer</span> <span class="id" type="var">v<sub>2</sub></span>)::(<span class="id" type="var">boxer</span> <span class="id" type="var">v<sub>3</sub></span>)::(<span class="id" type="var">boxer</span> <span class="id" type="var">v4</span>)::(<span class="id" type="var">boxer</span> <span class="id" type="var">v5</span>)<br/>
::(<span class="id" type="var">boxer</span> <span class="id" type="var">v6</span>)::(<span class="id" type="var">boxer</span> <span class="id" type="var">v7</span>)::(<span class="id" type="var">boxer</span> <span class="id" type="var">v8</span>)::(<span class="id" type="var">boxer</span> <span class="id" type="var">v9</span>)::(<span class="id" type="var">boxer</span> <span class="id" type="var">v10</span>)<br/>
::(<span class="id" type="var">boxer</span> <span class="id" type="var">v<sub>11</sub></span>)::(<span class="id" type="var">boxer</span> <span class="id" type="var">v<sub>12</sub></span>)::<span class="id" type="var">nil</span>)<br/>
(<span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0, <span class="id" type="var">v<sub>1</sub></span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0, <span class="id" type="var">v<sub>2</sub></span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0, <span class="id" type="var">v<sub>3</sub></span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0,<br/>
<span class="id" type="var">v4</span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0, <span class="id" type="var">v5</span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0, <span class="id" type="var">v6</span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0, <span class="id" type="var">v7</span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0,<br/>
<span class="id" type="var">v8</span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0, <span class="id" type="var">v9</span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0, <span class="id" type="var">v10</span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0, <span class="id" type="var">v<sub>11</sub></span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0,<br/>
<span class="id" type="var">v<sub>12</sub></span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0)<br/>
: <span class="id" type="var">ltac_scope</span>.<br/>
<span class="id" type="keyword">Notation</span> "'>>' v<sub>1</sub> v<sub>2</sub> v<sub>3</sub> v4 v5 v6 v7 v8 v9 v10 v<sub>11</sub> v<sub>12</sub> v13" :=<br/>
((<span class="id" type="var">boxer</span> <span class="id" type="var">v<sub>1</sub></span>)::(<span class="id" type="var">boxer</span> <span class="id" type="var">v<sub>2</sub></span>)::(<span class="id" type="var">boxer</span> <span class="id" type="var">v<sub>3</sub></span>)::(<span class="id" type="var">boxer</span> <span class="id" type="var">v4</span>)::(<span class="id" type="var">boxer</span> <span class="id" type="var">v5</span>)<br/>
::(<span class="id" type="var">boxer</span> <span class="id" type="var">v6</span>)::(<span class="id" type="var">boxer</span> <span class="id" type="var">v7</span>)::(<span class="id" type="var">boxer</span> <span class="id" type="var">v8</span>)::(<span class="id" type="var">boxer</span> <span class="id" type="var">v9</span>)::(<span class="id" type="var">boxer</span> <span class="id" type="var">v10</span>)<br/>
::(<span class="id" type="var">boxer</span> <span class="id" type="var">v<sub>11</sub></span>)::(<span class="id" type="var">boxer</span> <span class="id" type="var">v<sub>12</sub></span>)::(<span class="id" type="var">boxer</span> <span class="id" type="var">v13</span>)::<span class="id" type="var">nil</span>)<br/>
(<span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0, <span class="id" type="var">v<sub>1</sub></span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0, <span class="id" type="var">v<sub>2</sub></span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0, <span class="id" type="var">v<sub>3</sub></span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0,<br/>
<span class="id" type="var">v4</span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0, <span class="id" type="var">v5</span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0, <span class="id" type="var">v6</span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0, <span class="id" type="var">v7</span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0,<br/>
<span class="id" type="var">v8</span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0, <span class="id" type="var">v9</span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0, <span class="id" type="var">v10</span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0, <span class="id" type="var">v<sub>11</sub></span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0,<br/>
<span class="id" type="var">v<sub>12</sub></span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0, <span class="id" type="var">v13</span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0)<br/>
: <span class="id" type="var">ltac_scope</span>.<br/>
<br/>
</div>
<div class="doc">
The tactic <span class="inlinecode"><span class="id" type="var">list_boxer_of</span></span> inputs a term <span class="inlinecode"><span class="id" type="var">E</span></span> and returns a term
of type "list boxer", according to the following rules:
<div class="paragraph"> </div>
<ul class="doclist">
<li> if <span class="inlinecode"><span class="id" type="var">E</span></span> is already of type "list Boxer", then it returns <span class="inlinecode"><span class="id" type="var">E</span></span>;
</li>
<li> otherwise, it returns the list <span class="inlinecode">(<span class="id" type="var">boxer</span></span> <span class="inlinecode"><span class="id" type="var">E</span>)::<span class="id" type="var">nil</span></span>.
</li>
</ul>
</div>
<div class="code code-tight">
<br/>
<span class="id" type="keyword">Ltac</span> <span class="id" type="var">list_boxer_of</span> <span class="id" type="var">E</span> := <br/>
<span class="id" type="keyword">match</span> <span class="id" type="var">type</span> <span class="id" type="var">of</span> <span class="id" type="var">E</span> <span class="id" type="keyword">with</span> <br/>
| <span class="id" type="var">List.list</span> <span class="id" type="var">Boxer</span> ⇒ <span class="id" type="var">constr</span>:(<span class="id" type="var">E</span>)<br/>
| <span class="id" type="var">_</span> ⇒ <span class="id" type="var">constr</span>:((<span class="id" type="var">boxer</span> <span class="id" type="var">E</span>)::<span class="id" type="var">nil</span>)<br/>
<span class="id" type="keyword">end</span>.<br/>
<br/>
<span class="comment">(* ---------------------------------------------------------------------- *)</span><br/>
</div>
<div class="doc">
<a name="lab915"></a><h2 class="section">Databases of lemmas</h2>
<div class="paragraph"> </div>
Use the hint facility to implement a database mapping
terms to terms. To declare a new database, use a definition:
<span class="inlinecode"><span class="id" type="keyword">Definition</span></span> <span class="inlinecode"><span class="id" type="var">mydatabase</span></span> <span class="inlinecode">:=</span> <span class="inlinecode"><span class="id" type="var">True</span>.</span>
<div class="paragraph"> </div>
Then, to map <span class="inlinecode"><span class="id" type="var">mykey</span></span> to <span class="inlinecode"><span class="id" type="var">myvalue</span></span>, write the hint:
<span class="inlinecode"><span class="id" type="keyword">Hint</span></span> <span class="inlinecode"><span class="id" type="keyword">Extern</span></span> <span class="inlinecode">1</span> <span class="inlinecode">(<span class="id" type="var">Register</span></span> <span class="inlinecode"><span class="id" type="var">mydatabase</span></span> <span class="inlinecode"><span class="id" type="var">mykey</span>)</span> <span class="inlinecode">⇒</span> <span class="inlinecode"><span class="id" type="var">Provide</span></span> <span class="inlinecode"><span class="id" type="var">myvalue</span>.</span>
<div class="paragraph"> </div>
Finally, to query the value associated with a key, run the
tactic <span class="inlinecode"><span class="id" type="var">ltac_database_get</span></span> <span class="inlinecode"><span class="id" type="var">mydatabase</span></span> <span class="inlinecode"><span class="id" type="var">mykey</span></span>. This will leave
at the head of the goal the term <span class="inlinecode"><span class="id" type="var">myvalue</span></span>. It can then be
named and exploited using <span class="inlinecode"><span class="id" type="tactic">intro</span></span>.
</div>
<div class="code code-tight">
<br/>
<span class="id" type="keyword">Definition</span> <span class="id" type="var">ltac_database</span> (<span class="id" type="var">D</span>:<span class="id" type="var">Boxer</span>) (<span class="id" type="var">T</span>:<span class="id" type="var">Boxer</span>) (<span class="id" type="var">A</span>:<span class="id" type="var">Boxer</span>) := <span class="id" type="var">True</span>.<br/>
<br/>
<span class="id" type="keyword">Notation</span> "'Register' D T" := (<span class="id" type="var">ltac_database</span> (<span class="id" type="var">boxer</span> <span class="id" type="var">D</span>) (<span class="id" type="var">boxer</span> <span class="id" type="var">T</span>) <span class="id" type="var">_</span>) <br/>
(<span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 69, <span class="id" type="var">D</span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0, <span class="id" type="var">T</span> <span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 0).<br/>
<br/>
<span class="id" type="keyword">Lemma</span> <span class="id" type="var">ltac_database_provide</span> : <span style="font-family: arial;">∀</span>(<span class="id" type="var">A</span>:<span class="id" type="var">Boxer</span>) (<span class="id" type="var">D</span>:<span class="id" type="var">Boxer</span>) (<span class="id" type="var">T</span>:<span class="id" type="var">Boxer</span>),<br/>
<span class="id" type="var">ltac_database</span> <span class="id" type="var">D</span> <span class="id" type="var">T</span> <span class="id" type="var">A</span>.<br/>
<span class="id" type="keyword">Proof</span>. <span class="id" type="tactic">split</span>. <span class="id" type="keyword">Qed</span>.<br/>
<br/>
<span class="id" type="keyword">Ltac</span> <span class="id" type="var">Provide</span> <span class="id" type="var">T</span> := <span class="id" type="tactic">apply</span> (@<span class="id" type="var">ltac_database_provide</span> (<span class="id" type="var">boxer</span> <span class="id" type="var">T</span>)).<br/>
<br/>
<span class="id" type="keyword">Ltac</span> <span class="id" type="var">ltac_database_get</span> <span class="id" type="var">D</span> <span class="id" type="var">T</span> :=<br/>
<span class="id" type="keyword">let</span> <span class="id" type="var">A</span> := <span class="id" type="tactic">fresh</span> "TEMP" <span class="id" type="keyword">in</span> <span class="id" type="var">evar</span> (<span class="id" type="var">A</span>:<span class="id" type="var">Boxer</span>);<br/>
<span class="id" type="keyword">let</span> <span class="id" type="var">H</span> := <span class="id" type="tactic">fresh</span> "TEMP" <span class="id" type="keyword">in</span><br/>
<span class="id" type="tactic">assert</span> (<span class="id" type="var">H</span> : <span class="id" type="var">ltac_database</span> (<span class="id" type="var">boxer</span> <span class="id" type="var">D</span>) (<span class="id" type="var">boxer</span> <span class="id" type="var">T</span>) <span class="id" type="var">A</span>); <br/>
[ <span class="id" type="tactic">subst</span> <span class="id" type="var">A</span>; <span class="id" type="tactic">auto</span> <br/>
| <span class="id" type="tactic">subst</span> <span class="id" type="var">A</span>; <span class="id" type="keyword">match</span> <span class="id" type="var">type</span> <span class="id" type="var">of</span> <span class="id" type="var">H</span> <span class="id" type="keyword">with</span> <span class="id" type="var">ltac_database</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> (<span class="id" type="var">boxer</span> ?<span class="id" type="var">L</span>) ⇒<br/>
<span class="id" type="tactic">generalize</span> <span class="id" type="var">L</span> <span class="id" type="keyword">end</span>; <span class="id" type="tactic">clear</span> <span class="id" type="var">H</span> ].<br/>
<br/>
<span class="comment">(* ---------------------------------------------------------------------- *)</span><br/>
</div>
<div class="doc">
<a name="lab916"></a><h2 class="section">On-the-fly removal of hypotheses</h2>
<div class="paragraph"> </div>
In a list of arguments <span class="inlinecode">>></span> <span class="inlinecode"><span class="id" type="var">H1</span></span> <span class="inlinecode"><span class="id" type="var">H2</span></span> <span class="inlinecode">..</span> <span class="inlinecode"><span class="id" type="var">HN</span></span> passed to a tactic
such as <span class="inlinecode"><span class="id" type="var">lets</span></span> or <span class="inlinecode"><span class="id" type="var">applys</span></span> or <span class="inlinecode"><span class="id" type="var">forwards</span></span> or <span class="inlinecode"><span class="id" type="var">specializes</span></span>,
the term <span class="inlinecode"><span class="id" type="var">rm</span></span>, an identity function, can be placed in front
of the name of an hypothesis to be deleted.
</div>
<div class="code code-tight">
<br/>
<span class="id" type="keyword">Definition</span> <span class="id" type="var">rm</span> (<span class="id" type="var">A</span>:<span class="id" type="keyword">Type</span>) (<span class="id" type="var">X</span>:<span class="id" type="var">A</span>) := <span class="id" type="var">X</span>.<br/>
<br/>
</div>
<div class="doc">
<span class="inlinecode"><span class="id" type="var">rm_term</span></span> <span class="inlinecode"><span class="id" type="var">E</span></span> removes one hypothesis that admits the same
type as <span class="inlinecode"><span class="id" type="var">E</span></span>.
</div>
<div class="code code-tight">
<br/>
<span class="id" type="keyword">Ltac</span> <span class="id" type="var">rm_term</span> <span class="id" type="var">E</span> :=<br/>
<span class="id" type="keyword">let</span> <span class="id" type="var">T</span> := <span class="id" type="var">type</span> <span class="id" type="var">of</span> <span class="id" type="var">E</span> <span class="id" type="keyword">in</span><br/>
<span class="id" type="keyword">match</span> <span class="id" type="var">goal</span> <span class="id" type="keyword">with</span> <span class="id" type="var">H</span>: <span class="id" type="var">T</span> <span style="font-family: arial;">⊢</span> <span class="id" type="var">_</span> ⇒ <span class="id" type="tactic">try</span> <span class="id" type="tactic">clear</span> <span class="id" type="var">H</span> <span class="id" type="keyword">end</span>.<br/>
<br/>
</div>
<div class="doc">
<span class="inlinecode"><span class="id" type="var">rm_inside</span></span> <span class="inlinecode"><span class="id" type="var">E</span></span> calls <span class="inlinecode"><span class="id" type="var">rm_term</span></span> <span class="inlinecode"><span class="id" type="var">Ei</span></span> for any subterm
of the form <span class="inlinecode"><span class="id" type="var">rm</span></span> <span class="inlinecode"><span class="id" type="var">Ei</span></span> found in E
</div>
<div class="code code-tight">
<br/>
<span class="id" type="keyword">Ltac</span> <span class="id" type="var">rm_inside</span> <span class="id" type="var">E</span> :=<br/>
<span class="id" type="keyword">let</span> <span class="id" type="var">go</span> <span class="id" type="var">E</span> := <span class="id" type="var">rm_inside</span> <span class="id" type="var">E</span> <span class="id" type="keyword">in</span><br/>
<span class="id" type="keyword">match</span> <span class="id" type="var">E</span> <span class="id" type="keyword">with</span><br/>
| <span class="id" type="var">rm</span> ?<span class="id" type="var">X</span> ⇒ <span class="id" type="var">rm_term</span> <span class="id" type="var">X</span><br/>
| ?<span class="id" type="var">X1</span> ?<span class="id" type="var">X2</span> ⇒ <br/>
<span class="id" type="var">go</span> <span class="id" type="var">X1</span>; <span class="id" type="var">go</span> <span class="id" type="var">X2</span><br/>
| ?<span class="id" type="var">X1</span> ?<span class="id" type="var">X2</span> ?<span class="id" type="var">X3</span> ⇒ <br/>
<span class="id" type="var">go</span> <span class="id" type="var">X1</span>; <span class="id" type="var">go</span> <span class="id" type="var">X2</span>; <span class="id" type="var">go</span> <span class="id" type="var">X3</span><br/>
| ?<span class="id" type="var">X1</span> ?<span class="id" type="var">X2</span> ?<span class="id" type="var">X3</span> ?<span class="id" type="var">X4</span> ⇒ <br/>
<span class="id" type="var">go</span> <span class="id" type="var">X1</span>; <span class="id" type="var">go</span> <span class="id" type="var">X2</span>; <span class="id" type="var">go</span> <span class="id" type="var">X3</span>; <span class="id" type="var">go</span> <span class="id" type="var">X4</span><br/>
| ?<span class="id" type="var">X1</span> ?<span class="id" type="var">X2</span> ?<span class="id" type="var">X3</span> ?<span class="id" type="var">X4</span> ?<span class="id" type="var">X5</span> ⇒ <br/>
<span class="id" type="var">go</span> <span class="id" type="var">X1</span>; <span class="id" type="var">go</span> <span class="id" type="var">X2</span>; <span class="id" type="var">go</span> <span class="id" type="var">X3</span>; <span class="id" type="var">go</span> <span class="id" type="var">X4</span>; <span class="id" type="var">go</span> <span class="id" type="var">X5</span><br/>
| ?<span class="id" type="var">X1</span> ?<span class="id" type="var">X2</span> ?<span class="id" type="var">X3</span> ?<span class="id" type="var">X4</span> ?<span class="id" type="var">X5</span> ?<span class="id" type="var">X6</span> ⇒ <br/>
<span class="id" type="var">go</span> <span class="id" type="var">X1</span>; <span class="id" type="var">go</span> <span class="id" type="var">X2</span>; <span class="id" type="var">go</span> <span class="id" type="var">X3</span>; <span class="id" type="var">go</span> <span class="id" type="var">X4</span>; <span class="id" type="var">go</span> <span class="id" type="var">X5</span>; <span class="id" type="var">go</span> <span class="id" type="var">X6</span><br/>
| ?<span class="id" type="var">X1</span> ?<span class="id" type="var">X2</span> ?<span class="id" type="var">X3</span> ?<span class="id" type="var">X4</span> ?<span class="id" type="var">X5</span> ?<span class="id" type="var">X6</span> ?<span class="id" type="var">X7</span> ⇒ <br/>
<span class="id" type="var">go</span> <span class="id" type="var">X1</span>; <span class="id" type="var">go</span> <span class="id" type="var">X2</span>; <span class="id" type="var">go</span> <span class="id" type="var">X3</span>; <span class="id" type="var">go</span> <span class="id" type="var">X4</span>; <span class="id" type="var">go</span> <span class="id" type="var">X5</span>; <span class="id" type="var">go</span> <span class="id" type="var">X6</span>; <span class="id" type="var">go</span> <span class="id" type="var">X7</span><br/>
| ?<span class="id" type="var">X1</span> ?<span class="id" type="var">X2</span> ?<span class="id" type="var">X3</span> ?<span class="id" type="var">X4</span> ?<span class="id" type="var">X5</span> ?<span class="id" type="var">X6</span> ?<span class="id" type="var">X7</span> ?<span class="id" type="var">X8</span> ⇒ <br/>
<span class="id" type="var">go</span> <span class="id" type="var">X1</span>; <span class="id" type="var">go</span> <span class="id" type="var">X2</span>; <span class="id" type="var">go</span> <span class="id" type="var">X3</span>; <span class="id" type="var">go</span> <span class="id" type="var">X4</span>; <span class="id" type="var">go</span> <span class="id" type="var">X5</span>; <span class="id" type="var">go</span> <span class="id" type="var">X6</span>; <span class="id" type="var">go</span> <span class="id" type="var">X7</span>; <span class="id" type="var">go</span> <span class="id" type="var">X8</span><br/>
| ?<span class="id" type="var">X1</span> ?<span class="id" type="var">X2</span> ?<span class="id" type="var">X3</span> ?<span class="id" type="var">X4</span> ?<span class="id" type="var">X5</span> ?<span class="id" type="var">X6</span> ?<span class="id" type="var">X7</span> ?<span class="id" type="var">X8</span> ?<span class="id" type="var">X9</span> ⇒ <br/>
<span class="id" type="var">go</span> <span class="id" type="var">X1</span>; <span class="id" type="var">go</span> <span class="id" type="var">X2</span>; <span class="id" type="var">go</span> <span class="id" type="var">X3</span>; <span class="id" type="var">go</span> <span class="id" type="var">X4</span>; <span class="id" type="var">go</span> <span class="id" type="var">X5</span>; <span class="id" type="var">go</span> <span class="id" type="var">X6</span>; <span class="id" type="var">go</span> <span class="id" type="var">X7</span>; <span class="id" type="var">go</span> <span class="id" type="var">X8</span>; <span class="id" type="var">go</span> <span class="id" type="var">X9</span><br/>
| ?<span class="id" type="var">X1</span> ?<span class="id" type="var">X2</span> ?<span class="id" type="var">X3</span> ?<span class="id" type="var">X4</span> ?<span class="id" type="var">X5</span> ?<span class="id" type="var">X6</span> ?<span class="id" type="var">X7</span> ?<span class="id" type="var">X8</span> ?<span class="id" type="var">X9</span> ?<span class="id" type="var">X10</span> ⇒ <br/>
<span class="id" type="var">go</span> <span class="id" type="var">X1</span>; <span class="id" type="var">go</span> <span class="id" type="var">X2</span>; <span class="id" type="var">go</span> <span class="id" type="var">X3</span>; <span class="id" type="var">go</span> <span class="id" type="var">X4</span>; <span class="id" type="var">go</span> <span class="id" type="var">X5</span>; <span class="id" type="var">go</span> <span class="id" type="var">X6</span>; <span class="id" type="var">go</span> <span class="id" type="var">X7</span>; <span class="id" type="var">go</span> <span class="id" type="var">X8</span>; <span class="id" type="var">go</span> <span class="id" type="var">X9</span>; <span class="id" type="var">go</span> <span class="id" type="var">X10</span><br/>
| <span class="id" type="var">_</span> ⇒ <span class="id" type="var">idtac</span><br/>
<span class="id" type="keyword">end</span>.<br/>
<br/>
</div>
<div class="doc">
For faster performance, one may deactivate <span class="inlinecode"><span class="id" type="var">rm_inside</span></span> by
replacing the body of this definition with <span class="inlinecode"><span class="id" type="var">idtac</span></span>.
</div>
<div class="code code-tight">
<br/>
<span class="id" type="keyword">Ltac</span> <span class="id" type="var">fast_rm_inside</span> <span class="id" type="var">E</span> :=<br/>
<span class="id" type="var">rm_inside</span> <span class="id" type="var">E</span>.<br/>
<br/>
<span class="comment">(* ---------------------------------------------------------------------- *)</span><br/>
</div>
<div class="doc">
<a name="lab917"></a><h2 class="section">Numbers as arguments</h2>
<div class="paragraph"> </div>
When tactic takes a natural number as argument, it may be
parsed either as a natural number or as a relative number.
In order for tactics to convert their arguments into natural numbers,
we provide a conversion tactic.
</div>
<div class="code code-tight">
<br/>
<span class="id" type="keyword">Require</span> <span class="id" type="var">BinPos</span> <span class="id" type="var">Coq.ZArith.BinInt</span>.<br/>
<br/>
<span class="id" type="keyword">Definition</span> <span class="id" type="var">ltac_nat_from_int</span> (<span class="id" type="var">x</span>:<span class="id" type="var">BinInt.Z</span>) : <span class="id" type="var">nat</span> :=<br/>
<span class="id" type="keyword">match</span> <span class="id" type="var">x</span> <span class="id" type="keyword">with</span><br/>
| <span class="id" type="var">BinInt.Z0</span> ⇒ 0%<span class="id" type="var">nat</span><br/>
| <span class="id" type="var">BinInt.Zpos</span> <span class="id" type="var">p</span> ⇒ <span class="id" type="var">BinPos.nat_of_P</span> <span class="id" type="var">p</span><br/>
| <span class="id" type="var">BinInt.Zneg</span> <span class="id" type="var">p</span> ⇒ 0%<span class="id" type="var">nat</span><br/>
<span class="id" type="keyword">end</span>.<br/>
<br/>
<span class="id" type="keyword">Ltac</span> <span class="id" type="var">nat_from_number</span> <span class="id" type="var">N</span> :=<br/>
<span class="id" type="keyword">match</span> <span class="id" type="var">type</span> <span class="id" type="var">of</span> <span class="id" type="var">N</span> <span class="id" type="keyword">with</span><br/>
| <span class="id" type="var">nat</span> ⇒ <span class="id" type="var">constr</span>:(<span class="id" type="var">N</span>)<br/>
| <span class="id" type="var">BinInt.Z</span> ⇒ <span class="id" type="keyword">let</span> <span class="id" type="var">N'</span> := <span class="id" type="var">constr</span>:(<span class="id" type="var">ltac_nat_from_int</span> <span class="id" type="var">N</span>) <span class="id" type="keyword">in</span> <span class="id" type="var">eval</span> <span class="id" type="tactic">compute</span> <span class="id" type="keyword">in</span> <span class="id" type="var">N'</span><br/>
<span class="id" type="keyword">end</span>.<br/>
<br/>
</div>
<div class="doc">
<span class="inlinecode"><span class="id" type="var">ltac_pattern</span></span> <span class="inlinecode"><span class="id" type="var">E</span></span> <span class="inlinecode"><span class="id" type="tactic">at</span></span> <span class="inlinecode"><span class="id" type="var">K</span></span> is the same as <span class="inlinecode"><span class="id" type="tactic">pattern</span></span> <span class="inlinecode"><span class="id" type="var">E</span></span> <span class="inlinecode"><span class="id" type="tactic">at</span></span> <span class="inlinecode"><span class="id" type="var">K</span></span> except that
<span class="inlinecode"><span class="id" type="var">K</span></span> is a Coq natural rather than a Ltac integer. Syntax
<span class="inlinecode"><span class="id" type="var">ltac_pattern</span></span> <span class="inlinecode"><span class="id" type="var">E</span></span> <span class="inlinecode"><span class="id" type="keyword">as</span></span> <span class="inlinecode"><span class="id" type="var">K</span></span> <span class="inlinecode"><span class="id" type="keyword">in</span></span> <span class="inlinecode"><span class="id" type="var">H</span></span> is also available.
</div>
<div class="code code-tight">
<br/>
<span class="id" type="keyword">Tactic Notation</span> "ltac_pattern" <span class="id" type="var">constr</span>(<span class="id" type="var">E</span>) "at" <span class="id" type="var">constr</span>(<span class="id" type="var">K</span>) :=<br/>
<span class="id" type="keyword">match</span> <span class="id" type="var">nat_from_number</span> <span class="id" type="var">K</span> <span class="id" type="keyword">with</span><br/>
| 1 ⇒ <span class="id" type="tactic">pattern</span> <span class="id" type="var">E</span> <span class="id" type="tactic">at</span> 1<br/>
| 2 ⇒ <span class="id" type="tactic">pattern</span> <span class="id" type="var">E</span> <span class="id" type="tactic">at</span> 2<br/>
| 3 ⇒ <span class="id" type="tactic">pattern</span> <span class="id" type="var">E</span> <span class="id" type="tactic">at</span> 3<br/>
| 4 ⇒ <span class="id" type="tactic">pattern</span> <span class="id" type="var">E</span> <span class="id" type="tactic">at</span> 4<br/>
| 5 ⇒ <span class="id" type="tactic">pattern</span> <span class="id" type="var">E</span> <span class="id" type="tactic">at</span> 5<br/>
| 6 ⇒ <span class="id" type="tactic">pattern</span> <span class="id" type="var">E</span> <span class="id" type="tactic">at</span> 6<br/>
| 7 ⇒ <span class="id" type="tactic">pattern</span> <span class="id" type="var">E</span> <span class="id" type="tactic">at</span> 7<br/>
| 8 ⇒ <span class="id" type="tactic">pattern</span> <span class="id" type="var">E</span> <span class="id" type="tactic">at</span> 8<br/>
<span class="id" type="keyword">end</span>.<br/>
<br/>
<span class="id" type="keyword">Tactic Notation</span> "ltac_pattern" <span class="id" type="var">constr</span>(<span class="id" type="var">E</span>) "at" <span class="id" type="var">constr</span>(<span class="id" type="var">K</span>) "in" <span class="id" type="var">hyp</span>(<span class="id" type="var">H</span>) :=<br/>
<span class="id" type="keyword">match</span> <span class="id" type="var">nat_from_number</span> <span class="id" type="var">K</span> <span class="id" type="keyword">with</span><br/>
| 1 ⇒ <span class="id" type="tactic">pattern</span> <span class="id" type="var">E</span> <span class="id" type="tactic">at</span> 1 <span class="id" type="keyword">in</span> <span class="id" type="var">H</span><br/>
| 2 ⇒ <span class="id" type="tactic">pattern</span> <span class="id" type="var">E</span> <span class="id" type="tactic">at</span> 2 <span class="id" type="keyword">in</span> <span class="id" type="var">H</span><br/>
| 3 ⇒ <span class="id" type="tactic">pattern</span> <span class="id" type="var">E</span> <span class="id" type="tactic">at</span> 3 <span class="id" type="keyword">in</span> <span class="id" type="var">H</span><br/>
| 4 ⇒ <span class="id" type="tactic">pattern</span> <span class="id" type="var">E</span> <span class="id" type="tactic">at</span> 4 <span class="id" type="keyword">in</span> <span class="id" type="var">H</span><br/>
| 5 ⇒ <span class="id" type="tactic">pattern</span> <span class="id" type="var">E</span> <span class="id" type="tactic">at</span> 5 <span class="id" type="keyword">in</span> <span class="id" type="var">H</span><br/>
| 6 ⇒ <span class="id" type="tactic">pattern</span> <span class="id" type="var">E</span> <span class="id" type="tactic">at</span> 6 <span class="id" type="keyword">in</span> <span class="id" type="var">H</span><br/>
| 7 ⇒ <span class="id" type="tactic">pattern</span> <span class="id" type="var">E</span> <span class="id" type="tactic">at</span> 7 <span class="id" type="keyword">in</span> <span class="id" type="var">H</span><br/>
| 8 ⇒ <span class="id" type="tactic">pattern</span> <span class="id" type="var">E</span> <span class="id" type="tactic">at</span> 8 <span class="id" type="keyword">in</span> <span class="id" type="var">H</span><br/>
<span class="id" type="keyword">end</span>.<br/>
<br/>
<span class="comment">(* ---------------------------------------------------------------------- *)</span><br/>
</div>
<div class="doc">
<a name="lab918"></a><h2 class="section">Testing tactics</h2>
<div class="paragraph"> </div>
<span class="inlinecode"><span class="id" type="var">show</span></span> <span class="inlinecode"><span class="id" type="var">tac</span></span> executes a tactic <span class="inlinecode"><span class="id" type="var">tac</span></span> that produces a result,
and then display its result.
</div>
<div class="code code-tight">
<br/>
<span class="id" type="keyword">Tactic Notation</span> "show" <span class="id" type="var">tactic</span>(<span class="id" type="var">tac</span>) :=<br/>
<span class="id" type="keyword">let</span> <span class="id" type="var">R</span> := <span class="id" type="var">tac</span> <span class="id" type="keyword">in</span> <span class="id" type="var">pose</span> <span class="id" type="var">R</span>.<br/>
<br/>
</div>
<div class="doc">
<span class="inlinecode"><span class="id" type="var">dup</span></span> <span class="inlinecode"><span class="id" type="var">N</span></span> produces <span class="inlinecode"><span class="id" type="var">N</span></span> copies of the current goal. It is useful
for building examples on which to illustrate behaviour of tactics.
<span class="inlinecode"><span class="id" type="var">dup</span></span> is short for <span class="inlinecode"><span class="id" type="var">dup</span></span> <span class="inlinecode">2</span>.
</div>
<div class="code code-tight">
<br/>
<span class="id" type="keyword">Lemma</span> <span class="id" type="var">dup_lemma</span> : <span style="font-family: arial;">∀</span><span class="id" type="var">P</span>, <span class="id" type="var">P</span> <span style="font-family: arial;">→</span> <span class="id" type="var">P</span> <span style="font-family: arial;">→</span> <span class="id" type="var">P</span>.<br/>
<span class="id" type="keyword">Proof</span>. <span class="id" type="tactic">auto</span>. <span class="id" type="keyword">Qed</span>.<br/>
<br/>
<span class="id" type="keyword">Ltac</span> <span class="id" type="var">dup_tactic</span> <span class="id" type="var">N</span> :=<br/>
<span class="id" type="keyword">match</span> <span class="id" type="var">nat_from_number</span> <span class="id" type="var">N</span> <span class="id" type="keyword">with</span><br/>
| 0 ⇒ <span class="id" type="var">idtac</span><br/>
| <span class="id" type="var">S</span> 0 ⇒ <span class="id" type="var">idtac</span><br/>
| <span class="id" type="var">S</span> ?<span class="id" type="var">N'</span> ⇒ <span class="id" type="tactic">apply</span> <span class="id" type="var">dup_lemma</span>; [ | <span class="id" type="var">dup_tactic</span> <span class="id" type="var">N'</span> ]<br/>
<span class="id" type="keyword">end</span>.<br/>
<br/>
<span class="id" type="keyword">Tactic Notation</span> "dup" <span class="id" type="var">constr</span>(<span class="id" type="var">N</span>) := <br/>
<span class="id" type="var">dup_tactic</span> <span class="id" type="var">N</span>.<br/>
<span class="id" type="keyword">Tactic Notation</span> "dup" := <br/>
<span class="id" type="var">dup</span> 2.<br/>
<br/>
<span class="comment">(* ---------------------------------------------------------------------- *)</span><br/>
</div>
<div class="doc">
<a name="lab919"></a><h2 class="section">Check no evar in goal</h2>
</div>
<div class="code code-space">
<br/>
<span class="id" type="keyword">Ltac</span> <span class="id" type="var">check_noevar</span> <span class="id" type="var">M</span> :=<br/>
<span class="id" type="keyword">match</span> <span class="id" type="var">M</span> <span class="id" type="keyword">with</span> <span class="id" type="var">M</span> ⇒ <span class="id" type="var">idtac</span> <span class="id" type="keyword">end</span>.<br/>
<br/>
<span class="id" type="keyword">Ltac</span> <span class="id" type="var">check_noevar_hyp</span> <span class="id" type="var">H</span> := <span class="comment">(* todo: imlement using check_noevar *)</span><br/>
<span class="id" type="keyword">let</span> <span class="id" type="var">T</span> := <span class="id" type="var">type</span> <span class="id" type="var">of</span> <span class="id" type="var">H</span> <span class="id" type="keyword">in</span><br/>
<span class="id" type="keyword">match</span> <span class="id" type="var">type</span> <span class="id" type="var">of</span> <span class="id" type="var">H</span> <span class="id" type="keyword">with</span> <span class="id" type="var">T</span> ⇒ <span class="id" type="var">idtac</span> <span class="id" type="keyword">end</span>.<br/>
<br/>
<span class="id" type="keyword">Ltac</span> <span class="id" type="var">check_noevar_goal</span> := <span class="comment">(* todo: imlement using check_noevar *)</span><br/>
<span class="id" type="keyword">match</span> <span class="id" type="var">goal</span> <span class="id" type="keyword">with</span> <span style="font-family: arial;">⊢</span> ?<span class="id" type="var">G</span> ⇒ <span class="id" type="keyword">match</span> <span class="id" type="var">G</span> <span class="id" type="keyword">with</span> <span class="id" type="var">G</span> ⇒ <span class="id" type="var">idtac</span> <span class="id" type="keyword">end</span> <span class="id" type="keyword">end</span>.<br/>
<br/>
<span class="comment">(* ---------------------------------------------------------------------- *)</span><br/>
</div>
<div class="doc">
<a name="lab920"></a><h2 class="section">Tagging of hypotheses</h2>
<div class="paragraph"> </div>
<span class="inlinecode"><span class="id" type="var">get_last_hyp</span></span> <span class="inlinecode"><span class="id" type="var">tt</span></span> is a function that returns the last hypothesis
at the bottom of the context. It is useful to obtain the default
name associated with the hypothesis, e.g.
<span class="inlinecode"><span class="id" type="tactic">intro</span>;</span> <span class="inlinecode"><span class="id" type="keyword">let</span></span> <span class="inlinecode"><span class="id" type="var">H</span></span> <span class="inlinecode">:=</span> <span class="inlinecode"><span class="id" type="var">get_last_hyp</span></span> <span class="inlinecode"><span class="id" type="var">tt</span></span> <span class="inlinecode"><span class="id" type="keyword">in</span></span> <span class="inlinecode"><span class="id" type="keyword">let</span></span> <span class="inlinecode"><span class="id" type="var">H'</span></span> <span class="inlinecode">:=</span> <span class="inlinecode"><span class="id" type="tactic">fresh</span></span> <span class="inlinecode">"<span class="id" type="var">P</span>"</span> <span class="inlinecode"><span class="id" type="var">H</span></span> <span class="inlinecode"><span class="id" type="keyword">in</span></span> <span class="inlinecode">...</span>
</div>
<div class="code code-tight">
<br/>
<span class="id" type="keyword">Ltac</span> <span class="id" type="var">get_last_hyp</span> <span class="id" type="var">tt</span> :=<br/>
<span class="id" type="keyword">match</span> <span class="id" type="var">goal</span> <span class="id" type="keyword">with</span> <span class="id" type="var">H</span>: <span class="id" type="var">_</span> <span style="font-family: arial;">⊢</span> <span class="id" type="var">_</span> ⇒ <span class="id" type="var">constr</span>:(<span class="id" type="var">H</span>) <span class="id" type="keyword">end</span>.<br/>
<br/>
<span class="comment">(* ---------------------------------------------------------------------- *)</span><br/>
</div>
<div class="doc">
<a name="lab921"></a><h2 class="section">Tagging of hypotheses</h2>
<div class="paragraph"> </div>
<span class="inlinecode"><span class="id" type="var">ltac_tag_subst</span></span> is a specific marker for hypotheses
which is used to tag hypotheses that are equalities to
be substituted.
</div>
<div class="code code-tight">
<br/>
<span class="id" type="keyword">Definition</span> <span class="id" type="var">ltac_tag_subst</span> (<span class="id" type="var">A</span>:<span class="id" type="keyword">Type</span>) (<span class="id" type="var">x</span>:<span class="id" type="var">A</span>) := <span class="id" type="var">x</span>.<br/>
<br/>
</div>
<div class="doc">
<span class="inlinecode"><span class="id" type="var">ltac_to_generalize</span></span> is a specific marker for hypotheses
to be generalized.
</div>
<div class="code code-tight">
<br/>
<span class="id" type="keyword">Definition</span> <span class="id" type="var">ltac_to_generalize</span> (<span class="id" type="var">A</span>:<span class="id" type="keyword">Type</span>) (<span class="id" type="var">x</span>:<span class="id" type="var">A</span>) := <span class="id" type="var">x</span>.<br/>
<br/>
<span class="id" type="keyword">Ltac</span> <span class="id" type="var">gen_to_generalize</span> :=<br/>
<span class="id" type="tactic">repeat</span> <span class="id" type="keyword">match</span> <span class="id" type="var">goal</span> <span class="id" type="keyword">with</span> <br/>
<span class="id" type="var">H</span>: <span class="id" type="var">ltac_to_generalize</span> <span class="id" type="var">_</span> <span style="font-family: arial;">⊢</span> <span class="id" type="var">_</span> ⇒ <span class="id" type="tactic">generalize</span> <span class="id" type="var">H</span>; <span class="id" type="tactic">clear</span> <span class="id" type="var">H</span> <span class="id" type="keyword">end</span>.<br/>
<br/>
<span class="id" type="keyword">Ltac</span> <span class="id" type="var">mark_to_generalize</span> <span class="id" type="var">H</span> :=<br/>
<span class="id" type="keyword">let</span> <span class="id" type="var">T</span> := <span class="id" type="var">type</span> <span class="id" type="var">of</span> <span class="id" type="var">H</span> <span class="id" type="keyword">in</span><br/>
<span class="id" type="var">change</span> <span class="id" type="var">T</span> <span class="id" type="keyword">with</span> (<span class="id" type="var">ltac_to_generalize</span> <span class="id" type="var">T</span>) <span class="id" type="keyword">in</span> <span class="id" type="var">H</span>.<br/>
<br/>
<span class="comment">(* ---------------------------------------------------------------------- *)</span><br/>
</div>
<div class="doc">
<a name="lab922"></a><h2 class="section">Deconstructing terms</h2>
<div class="paragraph"> </div>
<span class="inlinecode"><span class="id" type="var">get_head</span></span> <span class="inlinecode"><span class="id" type="var">E</span></span> is a tactic that returns the head constant of the
term <span class="inlinecode"><span class="id" type="var">E</span></span>, ie, when applied to a term of the form <span class="inlinecode"><span class="id" type="var">P</span></span> <span class="inlinecode"><span class="id" type="var">x1</span></span> <span class="inlinecode">...</span> <span class="inlinecode"><span class="id" type="var">xN</span></span>
it returns <span class="inlinecode"><span class="id" type="var">P</span></span>. If <span class="inlinecode"><span class="id" type="var">E</span></span> is not an application, it returns <span class="inlinecode"><span class="id" type="var">E</span></span>.
Warning: the tactic seems to loop in some cases when the goal is
a product and one uses the result of this function.
</div>
<div class="code code-tight">
<br/>
<span class="id" type="keyword">Ltac</span> <span class="id" type="var">get_head</span> <span class="id" type="var">E</span> :=<br/>
<span class="id" type="keyword">match</span> <span class="id" type="var">E</span> <span class="id" type="keyword">with</span><br/>
| ?<span class="id" type="var">P</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> ⇒ <span class="id" type="var">constr</span>:(<span class="id" type="var">P</span>)<br/>
| ?<span class="id" type="var">P</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> ⇒ <span class="id" type="var">constr</span>:(<span class="id" type="var">P</span>)<br/>
| ?<span class="id" type="var">P</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> ⇒ <span class="id" type="var">constr</span>:(<span class="id" type="var">P</span>)<br/>
| ?<span class="id" type="var">P</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> ⇒ <span class="id" type="var">constr</span>:(<span class="id" type="var">P</span>)<br/>
| ?<span class="id" type="var">P</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> ⇒ <span class="id" type="var">constr</span>:(<span class="id" type="var">P</span>) <br/>
| ?<span class="id" type="var">P</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> ⇒ <span class="id" type="var">constr</span>:(<span class="id" type="var">P</span>)<br/>
| ?<span class="id" type="var">P</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> ⇒ <span class="id" type="var">constr</span>:(<span class="id" type="var">P</span>)<br/>
| ?<span class="id" type="var">P</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> ⇒ <span class="id" type="var">constr</span>:(<span class="id" type="var">P</span>) <br/>
| ?<span class="id" type="var">P</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> ⇒ <span class="id" type="var">constr</span>:(<span class="id" type="var">P</span>) <br/>
| ?<span class="id" type="var">P</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> ⇒ <span class="id" type="var">constr</span>:(<span class="id" type="var">P</span>) <br/>
| ?<span class="id" type="var">P</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> ⇒ <span class="id" type="var">constr</span>:(<span class="id" type="var">P</span>) <br/>
| ?<span class="id" type="var">P</span> <span class="id" type="var">_</span> ⇒ <span class="id" type="var">constr</span>:(<span class="id" type="var">P</span>)<br/>
| ?<span class="id" type="var">P</span> ⇒ <span class="id" type="var">constr</span>:(<span class="id" type="var">P</span>)<br/>
<span class="id" type="keyword">end</span>.<br/>
<br/>
</div>
<div class="doc">
<span class="inlinecode"><span class="id" type="var">get_fun_arg</span></span> <span class="inlinecode"><span class="id" type="var">E</span></span> is a tactic that decomposes an application
term <span class="inlinecode"><span class="id" type="var">E</span></span>, ie, when applied to a term of the form <span class="inlinecode"><span class="id" type="var">X1</span></span> <span class="inlinecode">...</span> <span class="inlinecode"><span class="id" type="var">XN</span></span>
it returns a pair made of <span class="inlinecode"><span class="id" type="var">X1</span></span> <span class="inlinecode">..</span> <span class="inlinecode"><span class="id" type="var">X</span>(<span class="id" type="var">N</span>-1)</span> and <span class="inlinecode"><span class="id" type="var">XN</span></span>.
</div>
<div class="code code-tight">
<br/>
<span class="id" type="keyword">Ltac</span> <span class="id" type="var">get_fun_arg</span> <span class="id" type="var">E</span> :=<br/>
<span class="id" type="keyword">match</span> <span class="id" type="var">E</span> <span class="id" type="keyword">with</span><br/>
| ?<span class="id" type="var">X1</span> ?<span class="id" type="var">X2</span> ?<span class="id" type="var">X3</span> ?<span class="id" type="var">X4</span> ?<span class="id" type="var">X5</span> ?<span class="id" type="var">X6</span> ?<span class="id" type="var">X7</span> ?<span class="id" type="var">X</span> ⇒ <span class="id" type="var">constr</span>:((<span class="id" type="var">X1</span> <span class="id" type="var">X2</span> <span class="id" type="var">X3</span> <span class="id" type="var">X4</span> <span class="id" type="var">X5</span> <span class="id" type="var">X6</span>,<span class="id" type="var">X</span>))<br/>
| ?<span class="id" type="var">X1</span> ?<span class="id" type="var">X2</span> ?<span class="id" type="var">X3</span> ?<span class="id" type="var">X4</span> ?<span class="id" type="var">X5</span> ?<span class="id" type="var">X6</span> ?<span class="id" type="var">X</span> ⇒ <span class="id" type="var">constr</span>:((<span class="id" type="var">X1</span> <span class="id" type="var">X2</span> <span class="id" type="var">X3</span> <span class="id" type="var">X4</span> <span class="id" type="var">X5</span>,<span class="id" type="var">X</span>))<br/>
| ?<span class="id" type="var">X1</span> ?<span class="id" type="var">X2</span> ?<span class="id" type="var">X3</span> ?<span class="id" type="var">X4</span> ?<span class="id" type="var">X5</span> ?<span class="id" type="var">X</span> ⇒ <span class="id" type="var">constr</span>:((<span class="id" type="var">X1</span> <span class="id" type="var">X2</span> <span class="id" type="var">X3</span> <span class="id" type="var">X4</span>,<span class="id" type="var">X</span>)) <br/>
| ?<span class="id" type="var">X1</span> ?<span class="id" type="var">X2</span> ?<span class="id" type="var">X3</span> ?<span class="id" type="var">X4</span> ?<span class="id" type="var">X</span> ⇒ <span class="id" type="var">constr</span>:((<span class="id" type="var">X1</span> <span class="id" type="var">X2</span> <span class="id" type="var">X3</span>,<span class="id" type="var">X</span>))<br/>
| ?<span class="id" type="var">X1</span> ?<span class="id" type="var">X2</span> ?<span class="id" type="var">X3</span> ?<span class="id" type="var">X</span> ⇒ <span class="id" type="var">constr</span>:((<span class="id" type="var">X1</span> <span class="id" type="var">X2</span>,<span class="id" type="var">X</span>)) <br/>
| ?<span class="id" type="var">X1</span> ?<span class="id" type="var">X2</span> ?<span class="id" type="var">X</span> ⇒ <span class="id" type="var">constr</span>:((<span class="id" type="var">X1</span>,<span class="id" type="var">X</span>))<br/>
| ?<span class="id" type="var">X1</span> ?<span class="id" type="var">X</span> ⇒ <span class="id" type="var">constr</span>:((<span class="id" type="var">X1</span>,<span class="id" type="var">X</span>))<br/>
<span class="id" type="keyword">end</span>.<br/>
<br/>
<span class="comment">(* ---------------------------------------------------------------------- *)</span><br/>
</div>
<div class="doc">
<a name="lab923"></a><h2 class="section">Action at occurence and action not at occurence</h2>
<div class="paragraph"> </div>
<span class="inlinecode"><span class="id" type="var">ltac_action_at</span></span> <span class="inlinecode"><span class="id" type="var">K</span></span> <span class="inlinecode"><span class="id" type="var">of</span></span> <span class="inlinecode"><span class="id" type="var">E</span></span> <span class="inlinecode"><span class="id" type="tactic">do</span></span> <span class="inlinecode"><span class="id" type="var">Tac</span></span> isolates the <span class="inlinecode"><span class="id" type="var">K</span></span>-th occurence of <span class="inlinecode"><span class="id" type="var">E</span></span> in the
goal, setting it in the form <span class="inlinecode"><span class="id" type="var">P</span></span> <span class="inlinecode"><span class="id" type="var">E</span></span> for some named pattern <span class="inlinecode"><span class="id" type="var">P</span></span>,
then calls tactic <span class="inlinecode"><span class="id" type="var">Tac</span></span>, and finally unfolds <span class="inlinecode"><span class="id" type="var">P</span></span>. Syntax
<span class="inlinecode"><span class="id" type="var">ltac_action_at</span></span> <span class="inlinecode"><span class="id" type="var">K</span></span> <span class="inlinecode"><span class="id" type="var">of</span></span> <span class="inlinecode"><span class="id" type="var">E</span></span> <span class="inlinecode"><span class="id" type="keyword">in</span></span> <span class="inlinecode"><span class="id" type="var">H</span></span> <span class="inlinecode"><span class="id" type="tactic">do</span></span> <span class="inlinecode"><span class="id" type="var">Tac</span></span> is also available.
</div>
<div class="code code-tight">
<br/>
<span class="id" type="keyword">Tactic Notation</span> "ltac_action_at" <span class="id" type="var">constr</span>(<span class="id" type="var">K</span>) "of" <span class="id" type="var">constr</span>(<span class="id" type="var">E</span>) "do" <span class="id" type="var">tactic</span>(<span class="id" type="var">Tac</span>) :=<br/>
<span class="id" type="keyword">let</span> <span class="id" type="var">p</span> := <span class="id" type="tactic">fresh</span> <span class="id" type="keyword">in</span> <span class="id" type="var">ltac_pattern</span> <span class="id" type="var">E</span> <span class="id" type="tactic">at</span> <span class="id" type="var">K</span>;<br/>
<span class="id" type="keyword">match</span> <span class="id" type="var">goal</span> <span class="id" type="keyword">with</span> <span style="font-family: arial;">⊢</span> ?<span class="id" type="var">P</span> <span class="id" type="var">_</span> ⇒ <span class="id" type="tactic">set</span> (<span class="id" type="var">p</span>:=<span class="id" type="var">P</span>) <span class="id" type="keyword">end</span>;<br/>
<span class="id" type="var">Tac</span>; <span class="id" type="tactic">unfold</span> <span class="id" type="var">p</span>; <span class="id" type="tactic">clear</span> <span class="id" type="var">p</span>.<br/>
<br/>
<span class="id" type="keyword">Tactic Notation</span> "ltac_action_at" <span class="id" type="var">constr</span>(<span class="id" type="var">K</span>) "of" <span class="id" type="var">constr</span>(<span class="id" type="var">E</span>) "in" <span class="id" type="var">hyp</span>(<span class="id" type="var">H</span>) "do" <span class="id" type="var">tactic</span>(<span class="id" type="var">Tac</span>) :=<br/>
<span class="id" type="keyword">let</span> <span class="id" type="var">p</span> := <span class="id" type="tactic">fresh</span> <span class="id" type="keyword">in</span> <span class="id" type="var">ltac_pattern</span> <span class="id" type="var">E</span> <span class="id" type="tactic">at</span> <span class="id" type="var">K</span> <span class="id" type="keyword">in</span> <span class="id" type="var">H</span>;<br/>
<span class="id" type="keyword">match</span> <span class="id" type="var">type</span> <span class="id" type="var">of</span> <span class="id" type="var">H</span> <span class="id" type="keyword">with</span> ?<span class="id" type="var">P</span> <span class="id" type="var">_</span> ⇒ <span class="id" type="tactic">set</span> (<span class="id" type="var">p</span>:=<span class="id" type="var">P</span>) <span class="id" type="keyword">in</span> <span class="id" type="var">H</span> <span class="id" type="keyword">end</span>;<br/>
<span class="id" type="var">Tac</span>; <span class="id" type="tactic">unfold</span> <span class="id" type="var">p</span> <span class="id" type="keyword">in</span> <span class="id" type="var">H</span>; <span class="id" type="tactic">clear</span> <span class="id" type="var">p</span>.<br/>
<br/>
</div>
<div class="doc">
<span class="inlinecode"><span class="id" type="var">protects</span></span> <span class="inlinecode"><span class="id" type="var">E</span></span> <span class="inlinecode"><span class="id" type="tactic">do</span></span> <span class="inlinecode"><span class="id" type="var">Tac</span></span> temporarily assigns a name to the expression <span class="inlinecode"><span class="id" type="var">E</span></span>
so that the execution of tactic <span class="inlinecode"><span class="id" type="var">Tac</span></span> will not modify <span class="inlinecode"><span class="id" type="var">E</span></span>. This is
useful for instance to restrict the action of <span class="inlinecode"><span class="id" type="tactic">simpl</span></span>.
</div>
<div class="code code-tight">
<br/>
<span class="id" type="keyword">Tactic Notation</span> "protects" <span class="id" type="var">constr</span>(<span class="id" type="var">E</span>) "do" <span class="id" type="var">tactic</span>(<span class="id" type="var">Tac</span>) :=<br/>
<span class="comment">(* let x := fresh "TEMP" in sets_eq x: E; T; subst x. *)</span><br/>
<span class="id" type="keyword">let</span> <span class="id" type="var">x</span> := <span class="id" type="tactic">fresh</span> "TEMP" <span class="id" type="keyword">in</span> <span class="id" type="keyword">let</span> <span class="id" type="var">H</span> := <span class="id" type="tactic">fresh</span> "TEMP" <span class="id" type="keyword">in</span><br/>
<span class="id" type="tactic">set</span> (<span class="id" type="var">X</span> := <span class="id" type="var">E</span>) <span class="id" type="keyword">in</span> ×; <span class="id" type="tactic">assert</span> (<span class="id" type="var">H</span> : <span class="id" type="var">X</span> = <span class="id" type="var">E</span>) <span class="id" type="tactic">by</span> <span class="id" type="tactic">reflexivity</span>; <br/>
<span class="id" type="var">clearbody</span> <span class="id" type="var">X</span>; <span class="id" type="var">Tac</span>; <span class="id" type="tactic">subst</span> <span class="id" type="var">x</span>.<br/>
<br/>
<span class="id" type="keyword">Tactic Notation</span> "protects" <span class="id" type="var">constr</span>(<span class="id" type="var">E</span>) "do" <span class="id" type="var">tactic</span>(<span class="id" type="var">Tac</span>) "/" :=<br/>
<span class="id" type="var">protects</span> <span class="id" type="var">E</span> <span class="id" type="tactic">do</span> <span class="id" type="var">Tac</span>.<br/>
<br/>
<span class="comment">(* ---------------------------------------------------------------------- *)</span><br/>
</div>
<div class="doc">
<a name="lab924"></a><h2 class="section">An alias for <span class="inlinecode"><span class="id" type="var">eq</span></span></h2>
<div class="paragraph"> </div>
<span class="inlinecode"><span class="id" type="var">eq'</span></span> is an alias for <span class="inlinecode"><span class="id" type="var">eq</span></span> to be used for equalities in
inductive definitions, so that they don't get mixed with
equalities generated by <span class="inlinecode"><span class="id" type="tactic">inversion</span></span>.
</div>
<div class="code code-tight">
<br/>
<span class="id" type="keyword">Definition</span> <span class="id" type="var">eq'</span> := @<span class="id" type="var">eq</span>.<br/>
<br/>
<span class="id" type="keyword">Hint</span> <span class="id" type="keyword">Unfold</span> <span class="id" type="var">eq'</span>.<br/>
<br/>
<span class="id" type="keyword">Notation</span> "x '='' y" := (@<span class="id" type="var">eq'</span> <span class="id" type="var">_</span> <span class="id" type="var">x</span> <span class="id" type="var">y</span>) <br/>
(<span class="id" type="tactic">at</span> <span class="id" type="var">level</span> 70, <span class="id" type="var">arguments</span> <span class="id" type="tactic">at</span> <span class="id" type="var">next</span> <span class="id" type="var">level</span>).<br/>
<br/>
<span class="comment">(* ********************************************************************** *)</span><br/>
</div>
<div class="doc">
<a name="lab925"></a><h1 class="section">Backward and forward chaining</h1>
</div>
<div class="code code-space">
<br/>
<span class="comment">(* ---------------------------------------------------------------------- *)</span><br/>
</div>
<div class="doc">
<a name="lab926"></a><h2 class="section">Application</h2>
<div class="paragraph"> </div>
<span class="inlinecode"><span class="id" type="var">rapply</span></span> is a tactic similar to <span class="inlinecode"><span class="id" type="tactic">eapply</span></span> except that it is
based on the <span class="inlinecode"><span class="id" type="tactic">refine</span></span> tactics, and thus is strictly more
powerful (at least in theory :). In short, it is able to perform
on-the-fly conversions when required for arguments to match,
and it is able to instantiate existentials when required.
</div>
<div class="code code-tight">
<br/>
<span class="id" type="keyword">Tactic Notation</span> "rapply" <span class="id" type="var">constr</span>(<span class="id" type="var">t</span>) :=<br/>
<span class="id" type="var">first</span> <span class="comment">(* todo: les @ sont inutiles *)</span><br/>
[ <span class="id" type="var">eexact</span> (@<span class="id" type="var">t</span>)<br/>
| <span class="id" type="tactic">refine</span> (@<span class="id" type="var">t</span>)<br/>
| <span class="id" type="tactic">refine</span> (@<span class="id" type="var">t</span> <span class="id" type="var">_</span>) <br/>
| <span class="id" type="tactic">refine</span> (@<span class="id" type="var">t</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span>) <br/>
| <span class="id" type="tactic">refine</span> (@<span class="id" type="var">t</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span>)<br/>
| <span class="id" type="tactic">refine</span> (@<span class="id" type="var">t</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span>)<br/>
| <span class="id" type="tactic">refine</span> (@<span class="id" type="var">t</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span>)<br/>
| <span class="id" type="tactic">refine</span> (@<span class="id" type="var">t</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span>)<br/>
| <span class="id" type="tactic">refine</span> (@<span class="id" type="var">t</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span>)<br/>
| <span class="id" type="tactic">refine</span> (@<span class="id" type="var">t</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span>)<br/>
| <span class="id" type="tactic">refine</span> (@<span class="id" type="var">t</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span>)<br/>
| <span class="id" type="tactic">refine</span> (@<span class="id" type="var">t</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span>)<br/>
| <span class="id" type="tactic">refine</span> (@<span class="id" type="var">t</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span>)<br/>
| <span class="id" type="tactic">refine</span> (@<span class="id" type="var">t</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span>)<br/>
| <span class="id" type="tactic">refine</span> (@<span class="id" type="var">t</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span>)<br/>
| <span class="id" type="tactic">refine</span> (@<span class="id" type="var">t</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span>)<br/>
| <span class="id" type="tactic">refine</span> (@<span class="id" type="var">t</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span> <span class="id" type="var">_</span>)<br/>
].<br/>