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Hey Philipp,
This is a great idea and in can see where I could apply the capture idea. Thank you!
Regards ,
Dano
Am 23.03.2013 00:55 schröbte dan young:
Hello all,
Hi!
FIrst of all Lua is awesome! I'm a fairly newbie @ Lua and a total newbie
@ LPeg.
I'm trying to figure out how to do the following. FOr example, I have the
following strings, and I only want to match strings a and e.
a = 'disease_show/881/////'
b = 'disease_show/266/tests///'
c = 'disease_show/191/description////'
d = 'disease_show//description////'
e = 'disease_show/881/'
I don't know how to exclude anything that might have letters after the
digits and the slash (i.e... b and c)
disease_match = (P'disease_show/'*R'09'^1*P'/'^0)
= disease_match:match(a)22
return disease_match:match(b)18
return disease_match:match(c)18
return disease_match:match(d)nil
return disease_match:match(e)18
If you add a capture to your pattern, you can see exactly which parts of the strings are matched:
disease_match = (C(P'disease_show/'*R'09'^1*P'/'^0))
disease_show/881/////
disease_show/266/
disease_show/191/
nil
disease_show/881/
So it appears in this case you need something that works like '$' for regexes (anchor the pattern at the end of the string), and thats P(-1) or -P(1) in LPeg[1][2]:
disease_match = (P'disease_show/'*R'09'^1*P'/'^0*P(-1))
22
nil
nil
nil
18
[1]: http://www.inf.puc-rio.br/~roberto/lpeg/lpeg.html#op-p
[2]: http://www.inf.puc-rio.br/~roberto/lpeg/lpeg.html#op-unm
Regards,
Dano
HTH,
Philipp