Now its getting very clear. The example you wrote to remove last 4 is   $s =~ s{ (?: [|] [^|]*){4} \z }{}xms; and can be written also as   $s =~ s{ ( [|] [^|]*){4} \z }{}xms; But if we don't need $1 values we can use "?:". As you advised I read "perlretut". From that I understand the "\z" used to indicate the end of the line and "ms" used for detecting multiple lines and "\n". And the "x" is used for increasing the readability of code in regex using spaces

In reply to Re^10: how to remove a string from end of a line by ravi45722
in thread how to remove a string from end of a line by rpinnam

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.