Something like....

    /0x(?-i:[\da-f]{1,4})/

... should do the trick. Curlies are pretty slow, relatively speaking, though. You will achieve approximately equivalent results with

    /0x(?-i:[\da-f]+)/

except that this will also match "0xdeadbeefcafe" and the like (which might be considered a feature).

Note that you do not want to use, as suggested elsewhere in this thread:

    /0x[\da-f]{1,4}/i # or /0x[\da-f]+/i

...since that would allow 0X2a (note the uppercase X) which is not a legal hexadecimal definition.

• another intruder with the mooring in the heart of the Perl

In reply to Re: Regular expression for hexadecimal number by grinder
in thread Regular expression for hexadecimal number by isha

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