A simple way would be: 
s/\s/_/g;

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No need for a module for that. You can of course be more fancy and show newlines as \n or ^J, tabs as \t or ^I, etc. All trivial to do with a regexp.

In reply to Re: Perl module to show whitespaces? by JavaFan
in thread Perl module to show whitespaces? by ndinsmore

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