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# re2py $INPUT -o $OUTPUT
# This example shows how to combine reusable re2c blocks: two blocks
# ('colors' and 'fish') are merged into one. The 'salmon' rule occurs
# in both blocks; the 'fish' block takes priority because it is used
# earlier. Default rule * occurs in all three blocks; the local (not
# inherited) definition takes priority.
from enum import Enum
class Ans(Enum):
COLOR = 1
FISH = 2
DUNNO = 3
%{rules:colors
* { raise "ah" }
"red" | "salmon" | "magenta" { return Ans.COLOR }
%}
%{rules:fish
* { raise "oh" }
"haddock" | "salmon" | "eel" { return Ans.FISH }
%}
def lex(yyinput):
yycursor = 0
%{
re2c:yyfill:enable = 0;
re2c:indent:top = 1;
!use:fish;
!use:colors;
* { return Ans.DUNNO } // overrides inherited '*' rules
%}
assert lex(b"salmon") == Ans.FISH
assert lex(b"what?") == Ans.DUNNO
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