Hi Monks,

I want to create a regex object that can be used to match zero or more VHDL comments. A VHDL comment starts with '--' and continues until the end of the line or file. 

    my $c = qr/(?>--[^\n]*(?:\n|\z))/; # VHDL comment regex

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I want to use $c with different quantifiers, like $c, $c?, $c+ and $c*, depending on context. 
    # position 01234567 89
    my $str = "a --b x\n x";

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I want the following code to match at positions 2-9: 
    $str =~ m/$c* x/;

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But the following should not match at all: 
    $str =~ m/$c*x/;

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Unfortunately, when the regex fails to match 'x' the engine bumps along to a position inside the comment (which I'd like to skip) and eventually matches at position 6.

Any idea how to fix this?

In reply to How do I avoid regex engine bumping along inside an atomic pattern? by zemane

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