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A comment on Why Using .* in Regular Expressions Is Almost Never What You Actually Want. Parent comment

Re:Why Using .* in Regular Expressions Is Almost Never What ... by mhaymo on Wednesday June 04, 2014 @09:57AM (#7845533)
Roman numerals? I have never encountered a regex implementation where '\d' matches 'X'. It's certainly not the case for Javascript: http://regexpal.com/?flags=g&regex=\d%2B&input=10%0Ax%0AX%0A...
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Re:Why Using .* in Regular Expressions Is Almost Never What ... by mmastrac on Wednesday June 04, 2014 @10:06AM (#7845590)
There's a whole lot of these numeral characters in unicode, for example:

http://www.charbase.com/2169-unicode-roman-numeral-ten

(even more in http://www.charbase.com/block/number-forms)

I'm not sure if Javascript matches these in its \d pattern, however, but I think that most regexp engines default to the ascii [0-9] unless you are using \p{Number}.

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Re:Why Using .* in Regular Expressions Is Almost Never What ... by pyre on Wednesday June 04, 2014 @11:06AM (#7845953)
There's also the character classes in Unicode:

http://www.fileformat.info/info/unicode/category/index.htm

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Re:Why Using .* in Regular Expressions Is Almost Never What ... by fennecfoxen on Wednesday June 04, 2014 @10:55AM (#7845862)
> /\d/.test("\u2169")

false

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Re:Why Using .* in Regular Expressions Is Almost Never What ... by jaredmcateer on Wednesday June 04, 2014 @10:59AM (#7845896)
Ruby also does not match roman numerals with \d

http://rubular.com/r/bOCmLIfKdZ

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