diff --git a/pl/grammar.yap b/pl/grammar.yap
index 9a4c5dbab..8a9c91629 100644
--- a/pl/grammar.yap
+++ b/pl/grammar.yap
@@ -62,18 +62,18 @@ Grammar related built-in predicates:
 
 
 :- module( '$_grammar', [!/2,
--        (',')/4,
--        (->)/4,
--        ('.')/4,
--        (;)/4,
--        'C'/3,
--        []/2,
--        []/4,
--        (\+)/3,
--        phrase/2,
--        phrase/3,
--        {}/3,
--        ('|')/4]).
+         (',')/4,
+         (->)/4,
+         ('.')/4,
+         (;)/4,
+        'C'/3,
+        []/2,
+        []/4,
+        (\+)/3,
+        phrase/2,
+        phrase/3,
+        {}/3,
+        ('|')/4]).
 
 :- use_system_module( '$_errors', ['$do_error'/2]).