To get the perl verb 'prev', you need to install Acme::ChronoNaught, which has useful applications for horse racing and the stock market ;).

Seriously though, I think you have misunderstood the operation of the verbs 'last' and 'next'. The three verbs 'last', 'next' and 'redo' are control verbs - glorified goto. They cause execution to jump: out of the loop, into the next iteration, and to the start of the current iteration, respectively.

If you want the previous value of your index, you need to store it somewhere - in $prev declared outside the scope of the loop. Set this at the end of your loop, and next time round it will hold what you want.

Of course, if you are counting, you can always subtract 1.

--

Oh Lord, won’t you burn me a Knoppix CD ?
My friends all rate Windows, I must disagree.
Your powers of persuasion will set them all free,
So oh Lord, won’t you burn me a Knoppix CD ?
(Missquoting Janis Joplin)

In reply to Re: 'prev' in for loop by rinceWind
in thread 'prev' in for loop by kulls

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.