On Thu, Jan 01, 2009, Jeff Johnson wrote:
> On Jan 1, 2009, at 1:04 PM, Ralf S. Engelschall wrote:
>>>
>>> A little help vetting the RE's please ;-) My eyes are already tired
>>> from writing the toy script, RE's are more effective than XML at eye
>>> gouging.
>>
>> I propose the following three entries in "macros"...
>>
>> # STEP 1: Match the string and capture regex parts
>> # 1 2 3 4
>> # X ":" X "-"X ":"X
>> %evr_tuple_match ^(?:([^:-]+):)?([^:-]+)(?:-([^:-]+))?(?::([^:-]
>> +))?$
>
> A little more help please.
>
> I'm using POSIX extended RE's.
Oh, sorry. I silemtly assumed PCRE! But ok, a non-PCRE version is also
possible: we just have to replace the non-capturing parenthesis (?:..)
with regular ones and then just ignore them in the selection phase:
# STEP 1: Match the string and capture regex parts
# 2 3 5 7
# X ":" X "-"X ":"X
%evr_tuple_match ^(([^:-]+):)?([^:-]+)(-([^:-]+))?(:([^:-]+))?$
# STEP 2: Assemble <E,V,R,D> tuple from regex parts
# <E,V,R,D> case 1: case 2: case 3: case 4: case 5: case 6:
# X:X-X:X X:X-X X:X X: X-X X
%evr_tuple_select 2357 237_ 23__ 2___ _23_ __5_
# STEP 3: Configure the comparison order of the <E,V,R,D> tuple elements
%evr_tuple_order EVRD
This should do the trick with regular POSIX regular expressions, too.
Ralf S. Engelschall
r...@engelschall.com
www.engelschall.com
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