When I saw the regex expression \S+?, my first thought was that this is equivalent to \S*. But it isn’t, as a little experimentation shows.

Consulting the Camel Book (4th Edition, page 214), I found that + means “1 or more times maximally” and +? means “1 or more times minimally.”

So, the difference between the two forms is not whether they match: if one matches, both must match. The difference lies only in what is matched, and this is relevant only if this part is captured (or, just possibly, if efficiency is an issue).

Hope that helps,

Athanasius <°(((>< contra mundum Iustus alius egestas vitae, eros Piratica,

In reply to Re: Puzzled by regex by Athanasius
in thread Puzzled by regex by syphilis

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