diff --git a/src/grammar.y b/src/grammar.y
index 4c5e4e6..3e9bc44 100644
--- a/src/grammar.y
+++ b/src/grammar.y
@@ -107,17 +107,17 @@ prototype:
           L_PAREN EXTERNAL R_PAREN FUNCTION ID COLON ID;
 
 definition:
-          TYPE ID COLON dblock 
+          TYPE ID COLON dblock
         | TYPE ID COLON constant ARROW ID
-        //| function_declaration
+        | function_declaration
         | TYPE ID COLON id_or_types ARROW id_or_types
         | ID parameter ASSIGN sblock
         ;
 
-//function_declaration:
-        //  FUNCTION ID COLON ID
-        //| EXTERNAL FUNCTION ID COLON ID
-        //;
+function_declaration:
+          FUNCTION ID COLON ID
+        | EXTERNAL FUNCTION ID COLON ID
+        ;
 
 parameter:
           L_PAREN ID R_PAREN
@@ -194,9 +194,9 @@ expression:
         | expression EQUAL_TO expression {printf("equals check expression\n");}
         | assignable {printf("assignable expression\n");}
         | L_PAREN expression R_PAREN {printf("paren expression\n");}
-        | memOp assignable 
+        | memOp assignable
 	;
-   
+
 
 ablock:
           L_PAREN argument_list R_PAREN