macro-ify matching days and parts

src/day1.rs

@@ -1,7 +1,7 @@
 use std::collections::VecDeque;
 
 /// Increments count if each sample is larger than the previous.
-pub fn day1_p1(input: String) {
+pub fn part1(input: String) {
     let mut prev = None;
     let mut count: u32 = 0;
     for line in input.lines() {
@@ -22,7 +22,7 @@ pub fn day1_p1(input: String) {
 /// 3-sample windowing average (no need to average, just use sum here)
 ///
 /// We need to start comparing when we have all of
-pub fn day1_p2(input: String) {
+pub fn part2(input: String) {
     let mut storage = VecDeque::with_capacity(5);
     let mut count = 0;
 

src/main.rs

@@ -36,29 +36,7 @@ fn main() {
     let input = read_input(day).unwrap();
 
     // TODO macro-ify
-    match day {
+    match_days!(1, day1, 2, day2, 3, day3, 4, day4);
-        1 => match part {
-            1 => day1::day1_p1(input),
-            2 => day1::day1_p2(input),
-            _ => (),
-        },
-        2 => match part {
-            1 => day2::part1(input),
-            2 => day2::part2(input),
-            _ => (),
-        },
-        3 => match part {
-            1 => day3::part1(input),
-            2 => day3::part2(input),
-            _ => (),
-        },
-        4 => match part {
-            1 => day4::part1(input),
-            2 => day4::part2(input),
-            _ => (),
-        },
-        _ => println!("Day {} not completed yet!", day),
-    }
 }
 
 // TODO do the inputs ever change inside of a day?
@@ -66,3 +44,19 @@ fn main() {
 fn read_input(day: u8) -> std::io::Result<String> {
     std::fs::read_to_string(format!("inputs/day{}", day))
 }
+
+#[macro_export]
+macro_rules! match_days {
+    ( $($num:expr, $day:ident),* ) => {
+        match day {
+            $(
+            $num => match part {
+                1 => $day::part1(input),
+                2 => $day::part2(input),
+                _ => println!("Part {} invalid!", part),
+            },
+            )*
+            _ => println!("Day {} not completed yet!", day),
+        }
+    };
+}