feature: add impl-source-read-only editor-variable

[sakurawald]

To close issue: #1615

This option is enabled by default, to disable it, eval the form in init.lisp

(setf (lem:variable-value 'lem-core::impl-source-read-only :global) nil)

The typical value of source dir for sbcl implementation are:

• /usr/share/sbcl-source/src/code/ (installed via yay -S sbcl)
• ~/.roswell/src/sbcl-2.4.10/src/code/ (installed via roswell)

There may be a better function to decide if (current-directory) is part of implementation source directory.

[sakurawald]

I think the form (eval '(logical-pathname-translations "SYS")) should be eval in the target repl, not the host repl (the repl that running the lem editor).

[sakurawald]

Still i don't know how to send the eval form to the connected running repl, or maybe there is some better solutions to this.

[cxxxr]

Thank you for the PR.
This suggestion for improvement is wonderful.
I am also grateful that you actually made the suggestion into a PR.

Also, I have some comments and suggestions regarding the changes.
Thank you.

suggestion 1

What about separating the files?

I think it can be separated into a single function: make this particular directory read-only.

Then it seems to me that it would be better to separate each file/package.

;; src/ext/read-only-sources.lisp
(uiop:define-package :lem/read-only-sources
  (:use :cl :lem)
  ...)
(in-package :lem/read-only-sources)

...

(add-hook *switch-to-buffer-hook* 'on-switch-to-buffer)

suggestion 2

How about separating the definition of the rules for making it read-only from the hooks?

For example, the following macro defines a rule.

;; lisp-mode.lisp
(define-read-only-source sbcl-source (directory)
  (dolist (pattern (connection-system-file-patterns (current-connection)))
    (when (pathname-match-p directory pattern)
      (return t))))

The definition of this macro is placed in the same place as the hook.

;; src/ext/read-only-sources.lisp

(defvar *patterns* (make-hash-table :test 'equal))

(defun register-pattern (name function)
  (setf (gethash name *patterns*) function))

(defmacro define-read-only-source (name (directory) &body body)
  `(register-pattern ',name (lambda (,directory) ,@body)))

(defun read-only-source-p (directory)
  (maphash (lambda (name pattern)
             (declare (ignore name))
             (when (funcall pattern directory)
               (return-from read-only-source-p t)))
           *patterns*))

(defun on-switch-to-buffer (buffer)
  (when (and (variable-value 'read-only-sources :default buffer)
             (read-only-source-p (buffer-directory buffer)))
    (setf (buffer-read-only-p buffer) t)))

(add-hook *switch-to-buffer-hook* 'on-switch-to-buffer)

[sakurawald]

The Suggestion 1 would be good, to extract the feature into an extension, reducing the complexity of the core source.

The Suggestion 2 makes the read-only a facility to support other purpose, looks nice.

You can close this issue, if you have implement the source in your side.

[cxxxr]

You can close this issue, if you have implement the source in your side.

OK.
I have created the following PR
#1658

Please let me know if there are any deficiencies.