Fix mixed up parsing of integers/naturals

2 files changed, 5 insertions, 5 deletions

diff --git a/src/lexer.rs b/src/lexer.rs
index d396951..32e6abe 100644
--- a/src/lexer.rs
+++ b/src/lexer.rs
@@ -89,11 +89,11 @@ macro_rules! digits {
     }}
 }
 
-named!(natural<&str, usize>, preceded!(tag!("+"), digits!(usize, 10)));
+named!(natural<&str, usize>, digits!(usize, 10));
 named!(integral<&str, isize>, digits!(isize, 10));
 named!(integer<&str, isize>, alt!(
     preceded!(tag!("-"), map!(integral, |i: isize| -i)) |
-    integral
+    preceded!(tag!("+"), integral)
 ));
 named!(boolean<&str, bool>, alt!(
     value!(true, tag!("True")) |
diff --git a/src/parser.rs b/src/parser.rs
index 2e252b1..8416d9b 100644
--- a/src/parser.rs
+++ b/src/parser.rs
@@ -13,15 +13,15 @@ pub fn parse_expr(s: &str) -> Result<BoxExpr, ParseError>  {
 #[test]
 fn test_parse() {
     use crate::core::Expr::*;
-    println!("test {:?}", parse_expr("+3 + +5 * +10"));
+    println!("test {:?}", parse_expr("3 + 5 * 10"));
     assert!(parse_expr("22").is_ok());
     assert!(parse_expr("(22)").is_ok());
-    assert_eq!(parse_expr("+3 + +5 * +10").ok(),
+    assert_eq!(parse_expr("3 + 5 * 10").ok(),
                Some(Box::new(NaturalPlus(Box::new(NaturalLit(3)),
                                 Box::new(NaturalTimes(Box::new(NaturalLit(5)),
                                                       Box::new(NaturalLit(10))))))));
     // The original parser is apparently right-associative
-    assert_eq!(parse_expr("+2 * +3 * +4").ok(),
+    assert_eq!(parse_expr("2 * 3 * 4").ok(),
                Some(Box::new(NaturalTimes(Box::new(NaturalLit(2)),
                                  Box::new(NaturalTimes(Box::new(NaturalLit(3)),
                                                        Box::new(NaturalLit(4))))))));