Dear wise ones, I've seen a small number of posts in which new users are encouraged not to include a leading ampersand when calling their own user-written functions whose definitions share the same file. One such admonition went as far as saying not to include it "unless you know the difference between using it and not using it and are sure that what it does when you include it is really what you want". Yet I have not seen any explanation of what the difference is between including a leading ampersand and not including it. I've always used a leading ampersand when calling &my_function and have never noticed a problem. Why is the use of a leading ampersand discouraged? What is the difference between including one and not including one? Thank you.

In reply to why avoid & on function call by fireblood

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.