Khen1950fx,
Presumably, the distinction the OP is trying to make between chars and words has to do with matching the entire word as well as white space.

Perl Monks is the best
What    is the    best place to eat

should produce "is the best" regardless of white space
[download]

Have you ever seen the rain
I have never seen the rain

should produce "seen the rain" not "ever seen the rain"
[download]

String::LCSS_XS does not do this.