Using a backslash "escapes" the following character.

That's not entirely true in this case: if the first character following a backslash is a digit [0-7], the sequence of up to 3 octal digits following is the escape sequence, and the resulting octal number is converted to the character with that index:

  perl -wle '$s = "\100"; print ord($s)'
  64

[download]

Similarly, "\x" introduces a sequence of up to 2 hex digits, eg "\x3f". In Unicode-aware perls (perl-5.6.0 and later) you can also introduce codepoints above 255 by putting braces around the hex number:

  perl -wle '$s = "\x{1000}"; print ord($s)'
  4096

[download]

Hugo

In reply to Re: Re: What does \1 do? by hv
in thread What does \1 do? by Anonymous Monk

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.