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Hi I am trying to understand python code which has this regular expression re.compile(r'[ :]'). I tried quite a few strings and couldnt find one. Can someone please give example where a text matches this pattern.

Terminator
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    `[]` means "any character from between these brackets". So your expression will match any space or colon character. – khelwood Nov 28 '14 at 17:40
  • The reference post links to [How to back reference "inner" selections ( () ) in a regular expression?](http://stackoverflow.com/a/1553171) for character classes. – Martijn Pieters Nov 28 '14 at 17:42
  • There are only two strings the pattern matches. `' '` and `':'`. Depending on how you *use* the pattern, those strings can be part of a larger string. – Martijn Pieters Nov 28 '14 at 17:43

2 Answers2

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The expression simply matches a single space or a single : (or rather, a string containing either). That’s it. […] is a character class.

Konrad Rudolph
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The [] matches any of the characters in the brackets. So [ :] will match one character that is either a space or a colon.

So these strings would have a match:

"Hello World"
"Field 1:"
etc...

These would not

"This_string_has_no_spaces_or_colons"
"100100101"

Edit: For more info on regular expressions: https://docs.python.org/2/library/re.html

Bryce Siedschlaw
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