diff --git a/rasn-compiler/src/generator/rasn/mod.rs b/rasn-compiler/src/generator/rasn/mod.rs
index 56b3949..b70a2ea 100644
--- a/rasn-compiler/src/generator/rasn/mod.rs
+++ b/rasn-compiler/src/generator/rasn/mod.rs
@@ -171,6 +171,6 @@ impl Backend for Rasn {
     }
 
     fn generate(&self, tld: ToplevelDefinition) -> Result<String, GeneratorError> {
-        self.generate_tld(tld).and_then(|s| Ok(s.to_string()))
+        self.generate_tld(tld).map(|ts| ts.to_string())
     }
 }