Solve day 6

src/lib.rs

@@ -1 +1,29 @@
+use std::fmt::{Debug, Display};
+use std::str::FromStr;
 
+/// Parse a whitespace separated list of things.
+///
+/// Panics on parse error.
+pub fn parse_ws_separated<T>(s: &str) -> impl Iterator<Item = T> + '_
+where
+    T: FromStr,
+    <T as FromStr>::Err: Debug,
+{
+    s.split_ascii_whitespace().map(|s| s.parse().unwrap())
+}
+
+/// Concatenate two things.
+///
+/// Panics if the concatenation is not be parseable.
+///
+/// ```rust
+/// # use aoc2023::concat;
+/// assert_eq!(concat(123, 456), 123456);
+/// ```
+pub fn concat<T>(a: T, b: T) -> T
+where
+    T: Display + FromStr,
+    <T as FromStr>::Err: Debug,
+{
+    format!("{a}{b}").parse().unwrap()
+}