But the OP was trying to make sure that the string has exactly one slash at both ends. Your snippet does not check for multiple slashes nor does it do anything about missing ones. The "blanks" that have to be filled in your approach basically consistute the entire solution.

As for the performance, this is Perl, not C; a string is not just a pointer to a chunk of bytes in memory, but wrapped in a complex data structure, and so is substr's return value. Then there's the need to have a lot of explicit ops in the optree, and on the other hand, there's the many (though specific) optimizations the regex engine has enjoyed. Optimizing a highlevel language like Perl, if you even want to, is a very different science from optimizing a lowlevel language like C.

Makeshifts last the longest.

In reply to Re^5: Regex - one and only one / at beginning and end of file path by Aristotle
in thread Regex - one and only one / at beginning and end of file path by mikedshelton

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.