Perl Regular Expression simplification

Question

I want to simplify the following statement.

if($_=~/^([0-9a-fA-F][0-9a-fA-F][0-9a-fA-F][0-9a-fA-F][0-9a-fA-F])/)

Is there an alternate way I can write the above statement without repeating [0-9a-fA-F] n times ?

Answer 1

You can use Quantifiers

{n} Match exactly n times

if (/^([0-9a-fA-F]{5})/)

Similarly, you can use a POSIX character class

xdigit Any hexadecimal digit ("[0-9a-fA-F]").

if (/^([[:xdigit:]]{5})/)

Answer 2

尝试这个

if($_=~/^([0-9a-fA-F]{5})/)

Answer 3

甚至

if( /^([0-9a-fA-F]{5})/ )