In your second set of data, the "Xyz" causes the engine to start matching with the "X", but the rest of the string causes the match to fail, and thus the last read match is $1, i.e. "FOO". However, since the matching engine started a new match, the number of matched characters was reset, so that essentially there is only one valid character reported; hence, what's available in $1 is "F". Personally, I wouldn't rely on what is not matched in $1, but would rather re-evaluate the string should the initial match fail. YMMV. TMTOWTDI.

In reply to Re: What's happening to my $1? by Anonymous Monk
in thread What's happening to my $1? by Not_a_Number

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.