$checks{'data'} =~ s/\s+/ /g;
 # remove leading and trailing blanks
 $checks{'data'} =~ s/^\s+//;
 $checks{'data'} =~ s/\s+$//;

[download]
I'd do this in reverse order, so that you aren't substituting in a space that you're later going to remove. That's just a tiny amount of extra work. If the spaces are really spaces and not tabs, you can squeeze them using tr/ //s instead of s/\s+/ /g. 
$checks{'regex'} = $checks{'regex'} ? $checks{'regex'} : $default;

[download]
The common idiom for this is 
$checks{'regex'} ||= $default;

[download]
but be sure you mean that all false values should be replaced with default. You may have meant, instead 
exists($checks{'regex'}) or $checks{'regex'} = $default;

[download]
I note that regex is really expected to be a character class. It would be simple to take a real regex (qr// style) instead.
The PerlMonk tr/// Advocate

In reply to Re: Check user input - reimplementation by Roy Johnson
in thread Check user input - reimplementation by kiat

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.