combinators

src/combinators.rs

@@ -0,0 +1,18 @@
+use crate::Parser;
+
+pub fn repeated<P, I, O, E>(parser: P) -> impl Parser<I, Vec<O>, E>
+where
+    P: Parser<I, O, E>,
+    I: Copy,
+{
+    move |input: I| {
+        let mut acc = input;
+        let mut results = vec![];
+
+        while let Ok((item, rest)) = parser.parse(acc) {
+            results.push(item);
+            acc = rest;
+        }
+        Ok((results, acc))
+    }
+}

src/lib.rs

@@ -1,10 +1,12 @@
 #![allow(dead_code)] //TODO eventually turn this off
 mod choice;
+mod combinators;
 mod map;
 mod primitives;
 mod sequence;
 
 pub use choice::*;
+pub use combinators::*;
 pub use map::*;
 pub use primitives::*;
 pub use sequence::*;
@@ -65,4 +67,11 @@ mod tests {
         let output = parser.parse("abcd").unwrap();
         assert_eq!((59, "cd"), output);
     }
+
+    #[test]
+    fn test_combinators() {
+        let parser = sequence(map(repeated(literal_char('a')), |_| 10), literal_char('b'));
+        let output = parser.parse("aaaaaaaabcd").unwrap();
+        assert_eq! {((10, 'b'), "cd"), output};
+    }
 }