in reply to Re: Quarms with RegEx
in thread Quarms with RegEx

nice catch wise monk 
if ($curline !~ /^#\s/ or $curline !~ /^\s/)

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is logically equivalent to: 
if (1)

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because every string will either A.) not start with a '#' or B.) not start with a space.

Might I recommend a smarter regex rather than anding two simple ones together? 

if ($curline !~ /^#?\s/)

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-Blake

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Re: Re: Re: Quarms with RegEx
by busunsl (Vicar) on Aug 28, 2001 at 12:57 UTC 
    if ($curline !~ /^#?\s/)

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    That will not work, because a domain line looks like:
    #domain1

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    And that will not match your regex, so the condition is true, which is wrong.
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      Ok, what am I missing here.... 
      #!/usr/bin/perl -w
use strict;

for ('#abc',' abc','abc','# abc',' #abc') {
  my $v1 = ($_ !~ /^#\s/ and $_ !~ /^\s/) || 0;  # yours
  my $v2 = ($_ !~ /^#?\s/) || 0;                 # mine
  print "$v1 $v2 '$_'\n";
}

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      Output: 
      1 1 '#abc'
0 0 ' abc'
1 1 'abc'
0 0 '# abc'
0 0 ' #abc'

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      -Blake

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        Ahh, I see, you're right, I missed something in the original code.

        I think the original ($_ !~ /^#\s/ or $_ !~ /^\s/) was wrong in two ways:

        • First: the 'or' should be an 'and'
        • Second: I think the code should exclude domain-lines (#domain1) and empty lines.
        So it should have been $_ !~ /^#/ and $_ !~ /^\s/, which I had in mind and which can not be combined your way, but like /^[#\s]/ or <code>/^#|\s/.
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