From 5346caaf260890f6d29eef7e6744f117dd732164 Mon Sep 17 00:00:00 2001
From: Timothy Warren <twarren@nabancard.com>
Date: Fri, 16 Dec 2022 14:36:56 -0500
Subject: [PATCH] More fun with macros

---
 aoc-shared/src/grid.rs | 28 ++++++++++++++++++++++++++++
 day12/Cargo.lock       |  7 +++++++
 day12/Cargo.toml       |  1 +
 day8/src/main.rs       |  8 ++------
 4 files changed, 38 insertions(+), 6 deletions(-)

diff --git a/aoc-shared/src/grid.rs b/aoc-shared/src/grid.rs
index 7d2027e..f9d28ac 100644
--- a/aoc-shared/src/grid.rs
+++ b/aoc-shared/src/grid.rs
@@ -106,3 +106,31 @@ impl<T> Grid2d<T> for Grid<T> {
         &mut self.vec[start..=end]
     }
 }
+
+#[macro_export]
+/// Simplifies newtype wrapping of the `Grid` struct
+macro_rules! impl_grid_newtype {
+    ($($struct: tt, $target: path, $type: ty),* ) => {
+        $(
+            impl ::core::ops::Deref for $struct<$type> {
+                type Target = $target;
+
+                fn deref(&self) -> &Self::Target {
+                    &self.0
+                }
+            }
+
+            impl ::core::ops::DerefMut for $struct<$type> {
+                fn deref_mut(&mut self) -> &mut Self::Target {
+                    &mut self.0
+                }
+            }
+
+            impl $struct<$type> {
+                pub fn new(width: usize) -> Self {
+                    $struct(<$target>::new(width))
+                }
+            }
+        )*
+    }
+}
diff --git a/day12/Cargo.lock b/day12/Cargo.lock
index 5e9bbe3..dec816a 100644
--- a/day12/Cargo.lock
+++ b/day12/Cargo.lock
@@ -2,6 +2,13 @@
 # It is not intended for manual editing.
 version = 3
 
+[[package]]
+name = "aoc-shared"
+version = "0.1.0"
+
 [[package]]
 name = "day12"
 version = "0.1.0"
+dependencies = [
+ "aoc-shared",
+]
diff --git a/day12/Cargo.toml b/day12/Cargo.toml
index ba13763..ac51653 100644
--- a/day12/Cargo.toml
+++ b/day12/Cargo.toml
@@ -6,3 +6,4 @@ edition = "2021"
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
+aoc-shared = { path = "../aoc-shared"}
diff --git a/day8/src/main.rs b/day8/src/main.rs
index c12b500..be1ba90 100644
--- a/day8/src/main.rs
+++ b/day8/src/main.rs
@@ -1,4 +1,4 @@
-use aoc_shared::deref;
+use aoc_shared::impl_grid_newtype;
 use aoc_shared::grid::Grid as BaseGrid;
 use aoc_shared::grid::Grid2d;
 use std::collections::HashSet;
@@ -53,13 +53,9 @@ impl Tree {
 // 2. Implement the Deref trait for the wrapped struct
 #[derive(Debug)]
 pub struct Grid<T>(BaseGrid<T>);
-deref!(Grid<Tree>, BaseGrid<Tree>);
+impl_grid_newtype!(Grid, BaseGrid<Tree>, Tree);
 
 impl Grid<Tree> {
-    pub fn new(width: usize) -> Self {
-        Grid(BaseGrid::new(width))
-    }
-
     pub fn from_file_str(file_str: &'static str) -> Grid<Tree> {
         let lines: Vec<&str> = file_str.lines().collect();
         let width = lines[0].len();