I tried unsuccessfully doing this with map. ...

You're running into two pitfalls. A slight rewrite might make it clearer. Consider:

@my_array_2 = map { s/^CHOP_ME_OFF_//g } @my_array;

[download]
But this won't work. It gives you an array full of integers, and it modifies the contents of @my_array.

In this case, it's better to use substr. 

@my_array_2 = map { 
   /^CHOP_ME_OFF_/ ?
      substr($_, length("CHOP_ME_OFF_")) : $_
} @my_array;

[download]

Update: On reflection, might be better off localizing $_ 

@my_array_2 = map { local $_ = $_; s/^CHOP_ME_OFF_//; $_ } @my_array;

[download]

In reply to Re: how could I use map here? by dws
in thread how could I use map here? by LameNerd

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.