splice is the preferred tool in Perl for managing chunks of arrays. Consider:

use strict; use warnings; my $test = ''; while (<DATA>) { if (! /^\d+$/) { $test .= $_; next; } chomp; my $n = $_; my @words = split /\s+/, $test; my @lines; # Use splice to pull out the desired lines push @lines, [splice @words, 0, $n] while @words; print "@$_\n" for @lines; } __DATA__ A huge string separated by lots and lots of words that I'd like to bre +ak up into n shorter strings of length y. This is stored in a __DATA__ secti +on to make a stand alone test program. Note that lines containing only a number provide an 'n' like the 10 on + the following line. 10 Note too that you can add more text that will be added and processed b +y any subsequent 'n' lines. 12

Prints:

A huge string separated by lots and lots of words that I'd like to break up into n shorter strings of length y. This is stored in a __DATA__ section to make a stand alone test program. Note that lines containing only a number provide an 'n' like the 10 on the following line. A huge string separated by lots and lots of words that I'd like to break up into n shorter strings of length y. This is stored in a __DATA__ section to make a stand alone test program. Note that lines containing only a number provide an 'n' like the 10 on the following line. Note too that you can add more text that will be added and processed by any subsequent 'n' lines.

which nicely gets rid of all those nasty C style for loops with their tricksy conditions and increments, and also removes the need for fussy slices and error prone indexes.

Perl's toolbox is pretty extensive and for some reason splice is often overlooked - it's worth knowing about.


DWIM is Perl's answer to Gödel

In reply to Re^2: A Little String Help Please by GrandFather
in thread A Little String Help Please by craigt

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.