From 0effd348e8ae8c9a2b5c173ab68a88ffe5678cb6 Mon Sep 17 00:00:00 2001
From: Dave Halter <davidhalter88@gmail.com>
Date: Wed, 15 Mar 2017 18:18:06 +0100
Subject: [PATCH] Add a note about the grammar creation.

---
 jedi/parser/pgen2/pgen.py | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/jedi/parser/pgen2/pgen.py b/jedi/parser/pgen2/pgen.py
index 0b5c4493..90fc63ca 100644
--- a/jedi/parser/pgen2/pgen.py
+++ b/jedi/parser/pgen2/pgen.py
@@ -382,5 +382,13 @@ class DFAState(object):
 
 
 def generate_grammar(bnf_text):
+    """
+    ``bnf_text`` is a grammar in extended BNF (using * for repetition, + for
+    at-least-once repetition, [] for optional parts, | for alternatives and ()
+    for grouping).
+
+    It's not EBNF according to ISO/IEC 14977. It's a dialect Python uses in its
+    own parser.
+    """
     p = ParserGenerator(bnf_text)
     return p.make_grammar()