The problem seems to be that $modifiers is not interpolated in time for the compiled regex to have seen it. This will work, 

if ( $text =~ m/(?$modifiers)$pattern/ ) {
    print "it matches\n";
}

[download]
That is a facet of "Cloistered Pattern Modifiers", as covered on p186 of the Camel Book(3ed.).

After Compline,
Zaxo

In reply to Re: Regular expression modifiers in a scalar by Zaxo
in thread Regular expression modifiers in a scalar by wintermte

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