Im try to match ip addresses and have come up with the following regular expression for python. I just cannot understand why this wont work. Any help would be greatly appreciated!
r"[0-255]\.[0-255]\.[0-255]\.[0-255]"
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Thomas Ayoub
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Darragh O'Flaherty
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2`[0-255]` will match only one of the single digits `0,1,2,5` – anubhava Apr 25 '17 at 16:38
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1And the `r""` will make the backslashes literal. You aren't escaping the dots – OneCricketeer Apr 25 '17 at 16:39
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1http://www.regular-expressions.info/ip.html – OneCricketeer Apr 25 '17 at 16:40
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This task is a rather poor fit for regular expressions. Try something like. `octets = address.split("."); valid = len(octets) == 4 and all(segment.isdigit() and int(segment) < 256 for segment in octets)`: ... – kindall Apr 25 '17 at 16:46
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Because [0-255] means any char between 0 to 2 or 5. switch to something like
r"^(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?).(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?).(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?).(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)$"
Thomas Ayoub
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@cricket_007 I'm not sure that leading 0's are forbidden with the norm. I'm gonna take a look – Thomas Ayoub Apr 25 '17 at 16:57