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DrChiper · 04-09-2018, 02:53 AM

Hi Kovid, you are absolutely right: (?<=M)\*M works.
But, that is not the expression I used

My expression also used a positive lookahead part

(?<=M)\s*(?=M)

which fails when \s* is empty. Further, when succeeding M<space>M text constructs are present after the very first MM construct, they are also not found, because the search is stopped immediately and the attached error message is displayed.

I use a text like: adasMMasd adssdM Masdda M Msad

Although my regex knowledge is limited, I cannot recall that there should be a limitation on the expected behavior when (assumed) greedy search would certainly be able to find the other M's ones.

Is there an explanation you know of?

Addation: I use the lookahead construct specifically in order to not "consume" the found text.

04-09-2018, 02:53 AM	#3
DrChiper Bookish Posts: 1,029 Karma: 2003162 Join Date: Jun 2011 Device: PC, t1, t2, t3, Clara BW, Clara HD, Libra 2, Libra Color, Nxtpaper 11	Hi Kovid, you are absolutely right: *(?<=M)\M works. But, that is not the expression I used My expression also used a positive lookahead part (?<=M)\s(?=M)* which fails when \s* is empty. Further, when succeeding M<space>M text constructs are present after the very first MM construct, they are also not found, because the search is stopped immediately and the attached error message is displayed. I use a text like: adasMMasd adssdM Masdda M Msad Although my regex knowledge is limited, I cannot recall that there should be a limitation on the expected behavior when (assumed) greedy search would certainly be able to find the other M's ones. Is there an explanation you know of? Addation: I use the lookahead construct specifically in order to not "consume" the found text. Attached Thumbnails Last edited by DrChiper; 04-09-2018 at 02:59 AM.