/usr/lib/python3.6/lib2to3/PatternGrammar.txt is in python3-lib2to3 3.6.5-3.
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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 | # Copyright 2006 Google, Inc. All Rights Reserved.
# Licensed to PSF under a Contributor Agreement.
# A grammar to describe tree matching patterns.
# Not shown here:
# - 'TOKEN' stands for any token (leaf node)
# - 'any' stands for any node (leaf or interior)
# With 'any' we can still specify the sub-structure.
# The start symbol is 'Matcher'.
Matcher: Alternatives ENDMARKER
Alternatives: Alternative ('|' Alternative)*
Alternative: (Unit | NegatedUnit)+
Unit: [NAME '='] ( STRING [Repeater]
| NAME [Details] [Repeater]
| '(' Alternatives ')' [Repeater]
| '[' Alternatives ']'
)
NegatedUnit: 'not' (STRING | NAME [Details] | '(' Alternatives ')')
Repeater: '*' | '+' | '{' NUMBER [',' NUMBER] '}'
Details: '<' Alternatives '>'
|