diff --git a/autogen/src/binary.rs b/autogen/src/binary.rs
index 9a59c54..97393a9 100644
--- a/autogen/src/binary.rs
+++ b/autogen/src/binary.rs
@@ -14,9 +14,7 @@ fn get_decode_method(kind: &str) -> Ident {
         return as_ident("id");
     }
 
-    let mut kind = kind;
-    if kind.starts_with("Literal") {
-        kind = &kind["Literal".len()..];
+    if let Some(kind) = kind.strip_prefix("Literal") {
         if kind == "Integer" || kind == "Float" {
             return as_ident("bit32");
         }