1 files changed, 1 insertions, 1 deletions
diff --git a/src/type/mod.rs b/src/type/mod.rs
index 8977d85..e4c0841 100644
--- a/src/type/mod.rs
+++ b/src/type/mod.rs
@@ -91,7 +91,7 @@ impl Type {
     pub fn is_concrete(&self) -> Result<(), String> {
         match self {
             Integer => Ok(()),
-            Boolean => todo!(),
+            Boolean => Ok(()),
             Arrow(a, b) => b.is_concrete().and_then(|_ok| a.is_concrete()),
             List(v) => {
                 let mut res = Ok(());