2 files changed, 19 insertions, 9 deletions
diff --git a/rust/src/lambda.rs b/rust/src/lambda.rs
index 3c1c8b6..7601640 100644
--- a/rust/src/lambda.rs
+++ b/rust/src/lambda.rs
@@ -13,32 +13,42 @@ pub fn run(arg: &str) -> String {
 #[derive(Debug, PartialEq)]
 pub enum Value {
     Num(i32),
+    Bool(bool),
 }
 
 impl Display for Value {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         match self {
             Value::Num(i) => write!(f, "{}", i),
+            Value::Bool(b) => write!(f, "{}", b),
         }
     }
 }
 
 fn interpret(arg: &str) -> Value {
-    Value::Num(arg.parse().unwrap())
+    arg.parse::<i32>()
+        .map(Value::Num)
+        .or(arg.parse::<bool>().map(Value::Bool))
+        .unwrap()
 }
 
 #[cfg(test)]
 mod tests {
     use super::interpret;
-    use super::Value::Num;
-    // Bring the macros and other important things into scope.
+    use super::Value::*;
     use proptest::prelude::*;
 
     proptest! {
-        #[test]
-        fn interpret_integer_as_number(i in -1000i32..1000) {
-            let result = interpret(&i.to_string());
-            assert_eq!(Num(i), result);
-        }
+            #[test]
+            fn interpret_integer_as_number(i in -1000i32..1000) {
+                let result = interpret(&i.to_string());
+                assert_eq!(Num(i), result);
+            }
+
+    }
+    #[test]
+    fn interpret_truth_values_as_booleans() {
+        assert_eq!(Bool(true), interpret("true"));
+        assert_eq!(Bool(false), interpret("false"));
     }
 }
diff --git a/rust/tests/interpret_test.rs b/rust/tests/interpret_test.rs
index f0b5201..5c3108a 100644
--- a/rust/tests/interpret_test.rs
+++ b/rust/tests/interpret_test.rs
@@ -3,5 +3,5 @@ use lambda::run;
 #[test]
 fn interpreter_can_read_and_interpret_file() {
     let result = run("sample/test.txt");
-    assert_eq!("1", result);
+    assert_eq!("12", result);
 }