I would like to print out some previously-defined regular expressions in a compact format. The main thing I want to do is strip out the whitespace and comments from those defined with the /x modifier. So if I have two functionally identical regexes: 

  our $rgx_plain = qr/^([a-z]+)\d*$/;
  our $rgx_fancy = qr/
                       ^         # beginning of string
                       (         # begin cap $1
                         [a-z]+  #   one or more letters
                       )         # end cap $1
                       \d*       # optional digits
                       $         # end of string
                     /x;

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then I'd like to make a function clean_regex such that 

  say $rgx_plain;
  say clean_regex($rgx_fancy);

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both print the same thing. Ideally clean_regex is a no-op on regexes defined without the /x modifier, such that 

  say clean_regex($rgx_plain);

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also prints the same thing. I have hacked together something gross and terrible but I was hoping for something better, presumably asking the Regexp compiler what it has once it's done throwing away comments and whitespace.

Thanks!

In reply to How to strip comments and whitespace from a regex defined with /x? by jh

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