Squashing whitespace is most efficiently done with tr: 
$description =~ tr/ / /s;

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This will leave (at most) a single leading/trailing space if it exists, though. Want to squash all the internal spaces and lose the leading/trailing spaces? Try this one: 
$description = join ' ', split ' ', $description;

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Read up on join and split if you want to see why this works.

In reply to Re: help substituting whitespaces? by snax
in thread help substituting whitespaces? by Anonymous Monk

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