[ale] VI vs perl RE question

[Joe Knapka]

attriel wrote:

>>In vi and [e]grep, "?" means "the preceding expression may or may not be
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>present". It
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>>Perl, it apparently means "don't be greedy", though it really surprises
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>me that such a
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>>fundamental piece of RE syntax would be different in Perl. So the ? in
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>the original
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>>(Perl) RE was not redundant; it accomplishes what [^"]* does in the
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>non-Perl case:
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>>stopping at the next quote encountered.
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>Actually
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>([a-z]+)? means some number of lowercase letters.  Maybe.
>([a-z]+?)fred means lowercase letters up to the first occurrence of "fred"
>([a-z]+)fred looks for lowercase followed by fred, but not necessarily the
>first fred.
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Does + mean the same thing it does in grep/vi? That is, "one or more
of the preceding expression"?  If so, it appears "?" can mean
different things depending on how it's used: in the first example, above,
it seems to mean "the previous thing is optional", whereas in
the second example, it seems to mean "don't be greedy".

?

-- JK