Thank you for your reply. It raises a couple of questions in my mind. Firstly, why the difference between qr{(?x)...} and qr{...}x? I ran the following and, yes, it looks like there's no interpolation with qr{...}x

$ perl -wle'use re "debug"; $x = "foo\nbar"; qr/hullo #there $x/x'
Compiling REx `hullo #there $x'
size 4 Got 36 bytes for offset annotations.
first at 1
   1: EXACT <hullo>(4)
   4: END(0)
anchored `hullo' at 0 (checking anchored isall) minlen 5 
Offsets: [4]
        1[15] 0[0] 0[0] 16[0] 
Name "main::x" used only once: possible typo at -e line 1.
Freeing REx: `"hullo #there $x"'

[download]

(Although I can't say that I really understand most of the re 'debug' output :-)

Secondly, why would you want interpolation inside comments anyway? I can see that interpolating a newline into the comment would stop the comment after the newline but to my mind doing the interpolation in the first place is not what you might reasonably expect.

BTW, initialising $deCommafied before the qr{...} also silences the warning for reasons I now understand.

Cheers,

JohnGG

In reply to Re^2: A variable name in a regex comment triggers a warning by johngg
in thread A variable name in a regex comment triggers a warning by johngg

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