Main prints result of interpreter

2 files changed, 2 insertions, 2 deletions

diff --git a/rust/src/main.rs b/rust/src/main.rs
index f401886..cf9477c 100644
--- a/rust/src/main.rs
+++ b/rust/src/main.rs
@@ -3,5 +3,5 @@ use std::env::args;
 use lambda::run;
 
 fn main() {
-    run(&args().nth(1).unwrap());
+    println!("result: {}", run(&args().nth(1).unwrap()));
 }
diff --git a/rust/src/parser.rs b/rust/src/parser.rs
index 8f95ca9..459219c 100644
--- a/rust/src/parser.rs
+++ b/rust/src/parser.rs
@@ -10,7 +10,7 @@ enum Token {
 pub fn parse(arg: &str) -> Value {
     let mut tokens = tokenize(arg);
     let mut state = Vec::new();
-    parse_tokens(&mut tokens, &mut state).unwrap()
+    parse_tokens(&mut tokens, &mut state).unwrap_or_else(|_| panic!("Syntax) error: {}", arg))
 }
 
 fn parse_tokens(tokens: &mut [Token], state: &mut Vec<Value>) -> Result<Value, String> {