Perl module to visually debug regexes in-place

 Regexp::Debugger is a module that helps tame unruly regexes by
 providing live interactive run-time visualizations of any regex in a
 Perl code. The debugger allows one to track capture variables, follow
 recursive subpattern matches, set break-points within a regex match,
 and even step backwards through the matching process to work out
 exactly where things started going so horribly wrong.
 .
 When you load this module, any regex in the same lexical scope will be
 visually (and interactively) debugged as it matches.
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 In addition to the Perl module, the package also contains the
 module's commandline frontend rxrx.