Could the problem be that my $identifier variable itself includes the $brackets variable? Do I need to eval it or something to force it to interpolate it correctly?
No. No. 
$identifier = qr/(?<identifier> \w+($brackets)?( \s*(\.|->)(?&identifi
+er))?)/;

[download]

It seems you forgot /x there. Your last regex (in substitution) looks this when compiled:

(?^:((?^:(?<identifier> \w+... (etc)

And

     (?^:

means

Starting in Perl 5.14, a "^" (caret or circumflex accent) immediately after the "?" is a shorthand equivalent to "d-imsx".
So, whitespace in 
<identifier> \w+

[download]
is treated literally. At least, that's what I think, considering the absense of any examples of strings to match.

Also, stop writing complex regexes on one line. Perl doesn't have to be write-only, you know?

In reply to Re: Storing part of a regex in a variable by Anonymous Monk
in thread Storing part of a regex in a variable by jonneve

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