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# Generated by re2py
# 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
def lex(yyinput):
yycursor = 0
yystate = 0
while True:
match yystate:
case 0:
yych = yyinput[yycursor]
yycursor += 1
match yych:
case 0x65:
yystate = 3
continue
case 0x68:
yystate = 4
continue
case 0x6D:
yystate = 5
continue
case 0x72:
yystate = 6
continue
case 0x73:
yystate = 7
continue
case _:
yystate = 1
continue
case 1:
yystate = 2
continue
case 2:
return Ans.DUNNO
case 3:
yymarker = yycursor
yych = yyinput[yycursor]
if yych == 0x65:
yycursor += 1
yystate = 8
continue
yystate = 2
continue
case 4:
yymarker = yycursor
yych = yyinput[yycursor]
if yych == 0x61:
yycursor += 1
yystate = 10
continue
yystate = 2
continue
case 5:
yymarker = yycursor
yych = yyinput[yycursor]
if yych == 0x61:
yycursor += 1
yystate = 11
continue
yystate = 2
continue
case 6:
yymarker = yycursor
yych = yyinput[yycursor]
if yych == 0x65:
yycursor += 1
yystate = 12
continue
yystate = 2
continue
case 7:
yymarker = yycursor
yych = yyinput[yycursor]
if yych == 0x61:
yycursor += 1
yystate = 13
continue
yystate = 2
continue
case 8:
yych = yyinput[yycursor]
if yych == 0x6C:
yycursor += 1
yystate = 14
continue
yystate = 9
continue
case 9:
yycursor = yymarker
yystate = 2
continue
case 10:
yych = yyinput[yycursor]
if yych == 0x64:
yycursor += 1
yystate = 15
continue
yystate = 9
continue
case 11:
yych = yyinput[yycursor]
if yych == 0x67:
yycursor += 1
yystate = 16
continue
yystate = 9
continue
case 12:
yych = yyinput[yycursor]
if yych == 0x64:
yycursor += 1
yystate = 17
continue
yystate = 9
continue
case 13:
yych = yyinput[yycursor]
if yych == 0x6C:
yycursor += 1
yystate = 18
continue
yystate = 9
continue
case 14:
return Ans.FISH
case 15:
yych = yyinput[yycursor]
if yych == 0x64:
yycursor += 1
yystate = 19
continue
yystate = 9
continue
case 16:
yych = yyinput[yycursor]
if yych == 0x65:
yycursor += 1
yystate = 20
continue
yystate = 9
continue
case 17:
return Ans.COLOR
case 18:
yych = yyinput[yycursor]
if yych == 0x6D:
yycursor += 1
yystate = 21
continue
yystate = 9
continue
case 19:
yych = yyinput[yycursor]
if yych == 0x6F:
yycursor += 1
yystate = 22
continue
yystate = 9
continue
case 20:
yych = yyinput[yycursor]
if yych == 0x6E:
yycursor += 1
yystate = 23
continue
yystate = 9
continue
case 21:
yych = yyinput[yycursor]
if yych == 0x6F:
yycursor += 1
yystate = 24
continue
yystate = 9
continue
case 22:
yych = yyinput[yycursor]
if yych == 0x63:
yycursor += 1
yystate = 25
continue
yystate = 9
continue
case 23:
yych = yyinput[yycursor]
if yych == 0x74:
yycursor += 1
yystate = 26
continue
yystate = 9
continue
case 24:
yych = yyinput[yycursor]
if yych == 0x6E:
yycursor += 1
yystate = 14
continue
yystate = 9
continue
case 25:
yych = yyinput[yycursor]
if yych == 0x6B:
yycursor += 1
yystate = 14
continue
yystate = 9
continue
case 26:
yych = yyinput[yycursor]
if yych == 0x61:
yycursor += 1
yystate = 17
continue
yystate = 9
continue
case _:
raise "internal lexer error"
assert lex(b"salmon") == Ans.FISH
assert lex(b"what?") == Ans.DUNNO
|
