Thanks...

What would be interesting, if anybody is up for it, is an actual concrete example of a nonreversible patttern, in either perl5 or perl6 syntax (or both). 

(?<=(a|aa))

[download]
is not permitted in perl5, because it is a variable length lookbehind. Glad to hear we get these in perl6.

Could someone throw out an example of what we can't do in perl6?

Maybe this is academic, but I like knowing the limits of pattern matching, as well as its power.

UPDATE: this seems to have just been answered, or at least a good attempt was made, by hv below, who must have been posting same time I was.

In reply to Re^2: What does it mean that a "pattern cannot be reversed?" by tphyahoo
in thread What does it mean that a "pattern cannot be reversed?" by tphyahoo

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