1 files changed, 18 insertions, 0 deletions

diff --git a/src/lisp/prelude.rs b/src/lisp/prelude.rs
index f5ff13a..e24ade5 100644
--- a/src/lisp/prelude.rs
+++ b/src/lisp/prelude.rs
@@ -437,5 +437,23 @@ pub fn new_env() -> Result<Environment, LispError> {
         }
     });
 
+    primitive!(env, Arity::Exact(2), "range", |args, _| {
+        if type_match!(
+            args,
+            0 => LispExpr::Number(LispNumber::Integer(_)),
+            1 => LispExpr::Number(LispNumber::Integer(_)))
+        {
+            let lower = args[0].unwrap_number().unwrap_integer();
+            let upper = args[1].unwrap_number().unwrap_integer();
+            Ok(LispExpr::List(
+                (lower..upper)
+                    .map(|i| LispExpr::Number(LispNumber::Integer(i)))
+                    .collect::<Vec<_>>(),
+            ))
+        } else {
+            Err(EvalError::TypeMismatch.into())
+        }
+    });
+
     Ok(env)
 }