The fastest way to n-tuple long strings is using unpack:

$text = 'howdoidoit';;

print for unpack '(a3X2)*', $text;;
how
owd
wdo
doi
oid
ido
doi
oit
it
it

print for unpack '(a4X3)*', $text;;
howd
owdo
wdoi
doid
oido
idoi
doit
oit
oit
oit

[download]

You have to discard the last n-1 results but that is very quick and simple to do.

With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'
Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
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In the absence of evidence, opinion is indistinguishable from prejudice.

In reply to Re^4: Exact string matching by BrowserUk
in thread Exact string matching by Anonymous Monk

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