diff --git a/docs/grammar.abnf b/docs/grammar.abnf
index 22fb652..0517348 100644
--- a/docs/grammar.abnf
+++ b/docs/grammar.abnf
@@ -4,7 +4,7 @@
 ;   - alternatives are ordered
 
 function-kind 	 = "proc" / "iter"
-proc-decl 		 = function-kind ident ["*"] "(" [proc-decl-args] ")" [":" ident] *stmt 'end'
+proc-decl 		 = function-kind ident ["*"] "(" [proc-decl-args] ")" [":" ident] *stmt "end"
 proc-decl-args 	 = symbol-type-pair *("," symbol-type-pair)
 symbol-type-pair = ident ":" ident