G'day perl-diddler,

"So how can I attach the "/g" modifier to my "qr" regex ... ?"
  1. Short answer: you can't so stop trying.
  2. Longer answer: read on ...

The 'g' modifier is used by m// and s/// to direct how a regex is to be used (single match, global substitution, etc.); it does not affect the regex itself. qr// has no 'g' modifier. Here's links to all three (note the modifier lists):

The 'g' modifier is not part of qr//'s syntax and, if used, syntax errors are raised (as expected). 

$ perl -wE 'my $re = qr{A}g'
Unknown regexp modifier "/g" at -e line 1, near "= "
Execution of -e aborted due to compilation errors.

[download]

You also can't do it with the re pragma's '/flags' mode: 

$ perl -wE 'use re "/g"'
Unknown regular expression flag "g" at -e line 1.

[download]

See also:

On a side note — related to what you're doing but not the current problem at hand — are you familiar with the '(?<flags>:<pattern>)' regex construct described in perlre: Extended Patterns: (?adluimnsx-imnsx:pattern)? This construct, and qr//'s interpolating, allows you to write something like this: 

$ perl -wE 'my ($p, $f) = (A => "x"); my $re = qr{(?$f: $p )}; say $re
+'
(?^u:(?x: A ))

[download]

Now you control the available flags and don't have to worry about qr//'s modifiers.

By the way, you can't add a 'g' modifier using this method either.  :-) 

$ perl -wE 'qr{(?g:)}'
Useless (?g) - use /g modifier in regex; marked by <-- HERE in m/(?g <
+-- HERE :)/ at -e line 1.

[download]

— Ken

In reply to Re: 'g' flag w/'qr' by kcott
in thread 'g' flag w/'qr' by perl-diddler

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