The other examples all handed off the first $n characters. But they didn't remove those first $n characters from the original $string, as the question required.

As always, there is more than one way to do it. For each of the examples below, assume the following setup:

my $string = "1234567890abcdefghijABCDEFGHIJK"; my $chars; my $n = 2;

With substr:

$chars = substr( $string, 0, $n ); substr( $string, 0, $n ) = "";

Another with substr:

( $chars, $string ) = ( substr($string,0,$n), substr($string,$n) );

And probaby the best substr solution:

$chars = substr ($string, 0, $n, "");

With a substitution s/// regexp:

$string = s/^(.{$n})(.*)$/$2/s; $chars = $1;

With split:

($chars, $string) = split /^(.{$n})/, $string, 1;

With a pattern match (m//):

($chars, $string) = $string =~ /^(.{$n})(.*)$/s;

With unpack (Not for the faint of heart):

( $chars, $string ) = unpack "a$n a@{[length($string)-$n]}", $string;


In reply to Re: How do I pull n characters off the front of a string? by davido
in thread How do I pull n characters off the front of a string? 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.