On Mon, 2 May 2011, ND wrote:
> Why when user ports to PCRE a successfull Perl pattern like
> (?=a(b))?.*d\1? (it's simplifyed version of real pattern used by my
> application)
> he need to look for difficulties to reconstruct it?
I have just committed a patch that allows quantifiers on parenthesized
assertions such as the example above. There are only three relevant
cases:
{0} never runs the assertion, but any groups inside it may be used
via code such as (?1)
{n,m} where n > 0 is in effect ignored: the assertion is run once
{0,n} is treated as {0,1}: the rest of the match is tried with and
without the assertion (the order depends on greediness).
I have NOT enabled quantifiers for assertions such as \b or ^ or $.
Philip
--
Philip Hazel
