diff --git a/grammar/declarations/function_declarations.bnf b/grammar/declarations/function_declarations.bnf
index a6ac2a7..530ad8c 100644
--- a/grammar/declarations/function_declarations.bnf
+++ b/grammar/declarations/function_declarations.bnf
@@ -11,8 +11,7 @@
 
 <required_parameter> ::= <identifier> ":" <parameter_type>
 
-<default_parameter> ::= <identifier> ":" <parameter_type> 
-    "=" <expression>
+<default_parameter> ::= <identifier> ".default(" <literal> ")"
 
 <lambda_declaration> ::= "fn" "(" <parameter_list>? ")" 
     "->" "[" <type> "]"