study only really helps (ie. saves time) if you are going to be searching the studied string multiple times to offset the cost of the studying itself. And then only if your search term contains one or more characters that have rare occurance in the studied string.

I've wondered whether study could be updated to take a parameter n, where it then builds the table from groups of n chars, triplets being more unique than doublets, and they more so than individual chars.

Of course, the regex engine would need updating to make use of the information, and that's a very scary task to comtemplate.

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In reply to Re: Would study help this regexps performance? by BrowserUk
in thread Surprisingly poor regex performance by sgifford

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