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# re2py $INPUT -o $OUTPUT -c
%{conditions %}
def parse_u32(yyinput):
yycursor = 0
yycond = YYC_INIT
num = 0
while True: %{
re2c:yyfill:enable = 0;
re2c:indent:top = 2;
<INIT> '0b' / [01] :=> BIN
<INIT> "0" :=> OCT
<INIT> "" / [1-9] :=> DEC
<INIT> '0x' / [0-9a-fA-F] :=> HEX
<INIT> * { return None }
<BIN> [01] {
num = num * 2 + (yyinput[yycursor - 1] - 48)
break
}
<OCT> [0-7] {
num = num * 8 + (yyinput[yycursor - 1] - 48)
break
}
<DEC> [0-9] {
num = num * 10 + (yyinput[yycursor - 1] - 48)
break
}
<HEX> [0-9] {
num = num * 16 + (yyinput[yycursor - 1] - 48)
break
}
<HEX> [a-f] {
num = num * 16 + (yyinput[yycursor - 1] - 87)
break
}
<HEX> [A-F] {
num = num * 16 + (yyinput[yycursor - 1] - 55)
break
}
<BIN, OCT, DEC, HEX> * { return num }
%}
assert parse_u32(b"\0") == None
assert parse_u32(b"1234567890\0") == 1234567890
assert parse_u32(b"0b1101\0") == 13
assert parse_u32(b"0x7Fe\0") == 2046
assert parse_u32(b"0644\0") == 420
assert parse_u32(b"9999999999\0") == 9999999999
|
