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# Generated by re2py
# re2py $INPUT -o $OUTPUT
# expect a null-terminated string
def lex(yyinput):
yycursor = 0
yylimit = len(yyinput) - 1 # terminating null not included
count = 0
while True:
yystate = 0
while True:
match yystate:
case 0:
yych = yyinput[yycursor]
if yych <= 0x20:
if yych <= 0x00:
if yylimit <= yycursor:
yystate = 9
continue
yycursor += 1
yystate = 1
continue
if yych >= 0x20:
yycursor += 1
yystate = 3
continue
yycursor += 1
yystate = 1
continue
else:
if yych == 0x27:
yycursor += 1
yystate = 5
continue
yycursor += 1
yystate = 1
continue
case 1:
yystate = 2
continue
case 2:
return -1
case 3:
yych = yyinput[yycursor]
if yych <= 0x00:
yystate = 4
continue
if yych == 0x20:
yycursor += 1
yystate = 3
continue
yystate = 4
continue
case 4:
break
case 5:
yymarker = yycursor
yych = yyinput[yycursor]
if yych >= 0x01:
yystate = 7
continue
if yylimit <= yycursor:
yystate = 2
continue
yycursor += 1
yystate = 6
continue
case 6:
yych = yyinput[yycursor]
yystate = 7
continue
case 7:
if yych <= 0x27:
if yych <= 0x00:
if yylimit <= yycursor:
yystate = 10
continue
yycursor += 1
yystate = 6
continue
if yych <= 0x26:
yycursor += 1
yystate = 6
continue
yycursor += 1
else:
if yych == 0x5C:
yycursor += 1
yystate = 8
continue
yycursor += 1
yystate = 6
continue
count += 1
break
case 8:
yych = yyinput[yycursor]
if yych <= 0x00:
if yylimit <= yycursor:
yystate = 10
continue
yycursor += 1
yystate = 6
continue
yycursor += 1
yystate = 6
continue
case 9:
return count
case 10:
yycursor = yymarker
yystate = 2
continue
case _:
raise "internal lexer error"
def test(str, count):
# termunating null not included in `lim`
assert count == lex(str)
test(b"\0", 0);
test(b"'qu\0tes' 'are' 'fine: \\'' \0", 3);
test(b"'unterminated\\'\0", -1)
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