"But is there some reason you couldn't have answered this yourself... or at least satisfied yourself that your code does or does not work?"
Firstly, thx for reply. It not work because just something wrong with my logic. Now I know the correct syntax, should be !~ but not !=~
furthermore want to ask, if I got keyword 
AB CDE         #don't know number of space between
AB     CDE     #5 space  =~ /AB.....CDE/
AB       CDE   #7 space  =~ /AB.......CDE/

[download]

If I do NOT know number of space between AB and CDE
what symbol should I use in this case? thank you!

In reply to Re: regular expression inverse match NOT match? by virtuemart2
in thread regular expression inverse match NOT match? by virtuemart2

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.