diff --git a/src/tokens.rs b/src/tokens.rs
index 2e6d58c..b75c32e 100644
--- a/src/tokens.rs
+++ b/src/tokens.rs
@@ -49,6 +49,7 @@ impl Tokens {
             "(" => Delimiter::Parenthesis,
             "[" => Delimiter::Bracket,
             "{" => Delimiter::Brace,
+            " " => Delimiter::None,
             _ => panic!("unknown delimiter: {}", delim),
         };
         let mut child = Tokens::new();