1 files changed, 13 insertions, 0 deletions
diff --git a/token/token.go b/token/token.go
index 92bc1ee..4cd3a3d 100644
--- a/token/token.go
+++ b/token/token.go
@@ -26,6 +26,19 @@ const (
 	LET      = "LET"
 )
 
+var keywords = map[string]TokenType{
+	"fn":  FUNCTION,
+	"let": LET,
+}
+
+func LookupIdentifier(ident string) TokenType {
+	if tok, ok := keywords[ident]; ok {
+		return tok
+	}
+
+	return IDENT
+}
+
 type TokenType string
 
 type Token struct {