s/\t||\r||\n||\f//g is not a very good regex, because it only matches a tab (\t) or the empty string (corresponding to the empty string between two vertical bars in the regex).

You probably meant something like s/[\t\r\n\f]//g

Or, if you want to replace any consecutive list of whitespaces with a a single blank: s/\s+/ /g

See perlretut for a gentle introduction.

I would be very grateful if anyone could explain where I need to put the substitution

you need to apply it to the variables that holds that text from which you want to strip the whitespaces. Since you wrote that script (at least you didn't attribute it to anybody else) you should know which one it is.

(Update: fixed character class, johngg++)

In reply to Re: Where to add substitution? by moritz
in thread Where to add substitution? by reclusivemonkey

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.