What you have currently should already interpolate, if I'm understanding what you mean by interpolate. You should get rid of some of those backslashes, though, because they're not needed. And change the "\s" on the right-hand side of the substitution into a " ". 
    $retVal =~ s/showpos"\svalue="1"/showpos" value="$main::pageVar1"/
+;

[download]
This works for me.

In reply to Re: Regex Interpolation by btrott
in thread Regex Interpolation by spectre

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