diff --git a/lib/api/src/externals/mod.rs b/lib/api/src/externals/mod.rs
index f21c99f14..c22941c03 100644
--- a/lib/api/src/externals/mod.rs
+++ b/lib/api/src/externals/mod.rs
@@ -42,6 +42,7 @@ impl Extern {
         }
     }
 
+    /// Create an `Extern` from an `Export`.
     pub fn from_export(store: &Store, export: Export) -> Extern {
         match export {
             Export::Function(f) => Extern::Function(Function::from_export(store, f)),