starting on day13, parser is halfway done

2022-aoc/Cargo.toml

@@ -12,3 +12,4 @@ lazy_static = "1.4.0"
 regex = "1.7"
 ndarray = "0.15"
 petgraph = "0.6"
+lyn = "0.1.0"

2022-aoc/src/d13.rs

@@ -0,0 +1,118 @@
+use aoc_runner_derive::{aoc as aoc_run, aoc_generator};
+use lyn::*;
+
+/*
+<packet> ::= <leftbrace> <list>? <rightbrace>
+<list> ::= <single> (<comma> <single>)*
+<single> ::= <number> | <leftbrace> <list>* <rightbrace>
+<comma> ::= "," | ", "
+<leftbrace> ::= "["
+<rightbrace> ::= "]"
+<number> ::= [0-9]+
+*/
+
+#[derive(PartialEq, Eq, PartialOrd, Ord, Debug)]
+struct Packet {
+    elements: Vec<Element>,
+}
+
+#[derive(Debug, PartialEq, Eq, Clone)]
+enum Element {
+    Plain(u32),
+    List(Vec<Element>),
+}
+
+impl PartialOrd for Element {
+    fn partial_cmp(&self, other: &Self) -> Option<std::cmp::Ordering> {
+        use Element::*;
+        match (self, other) {
+            (Plain(v1), Plain(v2)) => Some(v1.cmp(v2)),
+            (List(v1), List(v2)) => v1.partial_cmp(v2),
+            (Plain(_), List(_)) => List(vec![self.clone()]).partial_cmp(other),
+            (List(_), Plain(_)) => self.partial_cmp(&List(vec![other.clone()])),
+        }
+    }
+}
+
+impl Ord for Element {
+    fn cmp(&self, other: &Self) -> std::cmp::Ordering {
+        self.partial_cmp(other).unwrap()
+    }
+}
+
+#[aoc_generator(day13)]
+fn parse_input(input: &str) -> Vec<Packet> {
+    let mut out = Vec::new();
+    for line in input.lines() {
+        let mut scanner = Scanner::new(line);
+        let packet = parse_packet(&mut scanner);
+        out.push(packet);
+    }
+
+    out
+}
+
+fn parse_packet(scanner: &mut Scanner) -> Packet {
+    // we can pop the first character off, it's the opening brace
+    scanner.pop();
+    let elements = parse_list(scanner);
+    // pop off the last character, the final closing brace
+    assert!(scanner.pop().is_some());
+    assert!(scanner.is_done());
+    Packet { elements }
+}
+
+fn parse_list(scanner: &mut Scanner) -> Vec<Element> {
+    todo!()
+}
+
+#[aoc_run(day13, part1)]
+fn part1(input: &[Packet]) -> u32 {
+    0
+}
+
+#[aoc_run(day13, part2)]
+fn part2(input: &[Packet]) -> u32 {
+    0
+}
+
+#[cfg(test)]
+mod test {
+    use super::*;
+    const INPUT: &str = "[1,1,3,1,1]
+[1,1,5,1,1]
+
+[[1],[2,3,4]]
+[[1],4]
+
+[9]
+[[8,7,6]]
+
+[[4,4],4,4]
+[[4,4],4,4,4]
+
+[7,7,7,7]
+[7,7,7]
+
+[]
+[3]
+
+[[[]]]
+[[]]
+
+[1,[2,[3,[4,[5,6,7]]]],8,9]
+[1,[2,[3,[4,[5,6,0]]]],8,9]";
+
+    #[test]
+    fn part1_test() {
+        let v = parse_input(INPUT);
+
+        assert_eq!(part1(&v), 1);
+    }
+
+    #[test]
+    fn part2_test() {
+        let v = parse_input(INPUT);
+        assert_eq!(part2(&v), 1);
+    }
+}

2022-aoc/src/lib.rs

@@ -12,5 +12,6 @@ mod d9;
 mod d10;
 mod d11;
 mod d12;
+mod d13;
 
 aoc_lib! { year = 2022 }