Text::Wrap does this.

use Text::Wrap;

$Text::Wrap::columns = 70;

print Text::Wrap::fill( '', '', join '', <DATA> );

__DATA__
This is a huge paragraph that no doubt spans quite a number of columns
+. My guess is that it may even span past 70 Columns, so we'll use the
+ nifty Text::Wrap module to limit the number of columns that this par
+agraph can take up to 70.
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