Ok, as other replies have said the best way to do this is to not do this. :-) Use a hash in the first place when you think you will need "isamememberof" relationships.

But if you must do this for some reason then as the other replies have said you can use grep. Except that you probably dont want to do that. :-) grep() is slow for this type of job. grep() is intended for finding "all the members of an array that meet a set of criteria", but what you have asked for is "find if there is an element in the array that meets a set of criteria" which is pretty different. A simple (practically) textbook solution is 

my $found=0; 
$_==$scalar and ($found=1),last for @array;

[download]
Where $found will whether the array contains a value (in the case numerically) equivelent with $scalar. A way to do this as an expression (ie in the if you gave as an example) is here 
if (do {my $f=0; $_==$scalar and ($f=1),last for @array; $f}) {
}

[download]
Of course you could set it up in a sub or do any number of other things....

Remember using a hash in this situation is much smarter than using either this solution or grep()

--- demerphq
my friends call me, usually because I'm late....

In reply to Re: Set Operators by demerphq
in thread Set Operators 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.