From a74cd0241329ccab3c66a0afd626e055d726557a Mon Sep 17 00:00:00 2001
From: maneatingape <44142177+maneatingape@users.noreply.github.com>
Date: Thu, 31 Aug 2023 20:04:06 +0200
Subject: [PATCH] Refactor Point to implement From

---
 README.md             |  2 +-
 src/util/point.rs     | 19 +++++--------------
 src/year2015/day03.rs |  2 +-
 src/year2019/day03.rs |  4 ++--
 src/year2022/day09.rs |  9 +++------
 5 files changed, 12 insertions(+), 24 deletions(-)

diff --git a/README.md b/README.md
index 2437203..3907044 100644
--- a/README.md
+++ b/README.md
@@ -91,7 +91,7 @@ pie
 | 6 | [Tuning Trouble](https://adventofcode.com/2022/day/6) | [Source](src/year2022/day06.rs) | 6 |
 | 7 | [No Space Left On Device](https://adventofcode.com/2022/day/7) | [Source](src/year2022/day07.rs) | 10 |
 | 8 | [Treetop Tree House](https://adventofcode.com/2022/day/8) | [Source](src/year2022/day08.rs) | 55 |
-| 9 | [Rope Bridge](https://adventofcode.com/2022/day/9) | [Source](src/year2022/day09.rs) | 115 |
+| 9 | [Rope Bridge](https://adventofcode.com/2022/day/9) | [Source](src/year2022/day09.rs) | 122 |
 | 10 | [Cathode-Ray Tube](https://adventofcode.com/2022/day/10) | [Source](src/year2022/day10.rs) | 2 |
 | 11 | [Monkey in the Middle](https://adventofcode.com/2022/day/11) | [Source](src/year2022/day11.rs) | 2386 |
 | 12 | [Hill Climbing Algorithm](https://adventofcode.com/2022/day/12) | [Source](src/year2022/day12.rs) | 59 |
diff --git a/src/util/point.rs b/src/util/point.rs
index 9e6d733..8a9cfe1 100644
--- a/src/util/point.rs
+++ b/src/util/point.rs
@@ -84,10 +84,10 @@ impl Hash for Point {
     }
 }
 
-impl Point {
+impl From<u8> for Point {
     #[inline]
-    pub fn from_byte(b: u8) -> Point {
-        match b {
+    fn from(value: u8) -> Self {
+        match value {
             b'^' | b'U' => UP,
             b'v' | b'D' => DOWN,
             b'<' | b'L' => LEFT,
@@ -95,18 +95,9 @@ impl Point {
             _ => unreachable!(),
         }
     }
+}
 
-    #[inline]
-    pub fn from_string(s: &str) -> Point {
-        match s {
-            "U" => UP,
-            "D" => DOWN,
-            "L" => LEFT,
-            "R" => RIGHT,
-            _ => unreachable!(),
-        }
-    }
-
+impl Point {
     #[inline]
     pub fn clockwise(self) -> Point {
         Point { x: -self.y, y: self.x }
diff --git a/src/year2015/day03.rs b/src/year2015/day03.rs
index a3bf96a..7584e87 100644
--- a/src/year2015/day03.rs
+++ b/src/year2015/day03.rs
@@ -10,7 +10,7 @@ use crate::util::hash::*;
 use crate::util::point::*;
 
 pub fn parse(input: &str) -> Vec<Point> {
-    input.trim().bytes().map(Point::from_byte).collect()
+    input.trim().bytes().map(Point::from).collect()
 }
 
 pub fn part1(input: &[Point]) -> usize {
diff --git a/src/year2019/day03.rs b/src/year2019/day03.rs
index ae1f190..ab4d795 100644
--- a/src/year2019/day03.rs
+++ b/src/year2019/day03.rs
@@ -44,7 +44,7 @@ pub fn parse(input: &str) -> Input {
     let mut horizontal = BTreeMap::new();
 
     for (direction, amount) in steps(0) {
-        let delta = Point::from_byte(direction);
+        let delta = Point::from(direction);
         let end = start + delta * amount;
         let line = Line { start, end, distance };
 
@@ -65,7 +65,7 @@ pub fn parse(input: &str) -> Input {
     let mut delay = i32::MAX;
 
     for (direction, amount) in steps(1) {
-        let delta = Point::from_byte(direction);
+        let delta = Point::from(direction);
         let end = start + delta * amount;
 
         // Use a block to scope the `update` lamdbas mutable borrow of `distance`.
diff --git a/src/year2022/day09.rs b/src/year2022/day09.rs
index 06dedee..56842ba 100644
--- a/src/year2022/day09.rs
+++ b/src/year2022/day09.rs
@@ -3,7 +3,6 @@
 //! This solution relies on the [`Point`] utility class. Two dimensional problems are common in
 //! Advent of Code, so having a decent `Point` (or `Coord` or `Pos`) class in your back pocket
 //! is handy.
-use crate::util::iter::*;
 use crate::util::parse::*;
 use crate::util::point::*;
 
@@ -14,11 +13,9 @@ type Input = ([i32; 4], Vec<Pair>);
 /// magnitude respectively. Then determines the maximum extent of the head so that we can allocate
 /// a two dimensional grid.
 pub fn parse(input: &str) -> Input {
-    let pairs: Vec<_> = input
-        .split_ascii_whitespace()
-        .chunk::<2>()
-        .map(|[d, n]| (Point::from_string(d), n.signed()))
-        .collect();
+    let first = input.bytes().filter(u8::is_ascii_alphabetic).map(Point::from);
+    let second = input.iter_signed::<i32>();
+    let pairs = first.zip(second).collect();
 
     // Determine maximum extents
     let mut x1 = i32::MAX;