That’s a good point; paths could potentially be filled with rules that need to be broken down, re-defined often and remain well understood.
I would however argue whether or not it is a good idea to rely this heavily on paths in the first place, as it seems better suited for a schema. About object composition and schemas, this is what I’m picturing as an alternative to (my understanding of) pyparsing: Objects >>> project.shot(1000).used_assets() ['myasset1', 'myasset2'] As opposed to >>> path = '/projects/hulk/1000/used_assets/myasset1'>>> project, shot, assets >>> = parse(path) Schema As an alternative, a schema might be defined as: ['root', 'project', 'shot' ,'used_asset] Which would map each level of a hierarchy to the respective index. # For example $ /myprojects/hulk/1000/myasset1 $ 0 1 2 3 On 7 May 2014 12:02, Justin Israel <[email protected]> wrote: > But what if strings are exactly the thing you have to be dealing with? > Consider you are trying to design a way to parse paths in a VFX-style > pipeline. You define a naming convention that will be followed, which could > have different path strings depending on the specific context. Maybe > something like: > > /projects/<project>/<scene> /<shot> > /<type/stage>/<resolution_colorspace>/<version>/<file.ext> > > /projects/<project>/<asset.type>/<name>/<type/stage>/<resolution_colorspace|representation>/<version>/<file.ext> > > And maybe even the /project prefix is optional. > > I feel like what you might be suggesting in terms of objects, composition, > lists, ... ultimately is the same thing that pyparsing would be trying to > abstract for you. From what I have read in the docs, what you are getting > with pyparsing is grammar primitives, such as a "Word". A Word in this case > might be the format that defines asset.type. And then you take all of these > primatives combine them, in a reusable way, into the representation of > different paths. > > So if I defined words/regex for: > > > - project > - scene > - asset > - shot > - assetName > - type > - resolution > - colorspace > - version > - ... > > Then I can start combing those. Like taking a definition for resolution > and colorspace and saying <resolution>_<colorspace>, or being able to reuse > the definition for a project format across different path types. Or being > able to say the '/project' prefix is optional in terms of parsing the path. > > I too would like to see some examples from someone who has pyparsing > experience. But this is what I gleaned from looking over the wiki and docs. > Reusable definitions at the word level, to be combined/composed into > larger grammars that can be used to parse strings. After all...paths are > strings. Either you are going to define big regular expressions to break > down the variations of these paths, or you are going to hand roll a class > that has a bunch of branching code to split and parse the components, or > you are going to use a library like pyparsing to define grammar and let it > handle the parsing for you. > > > > > On Wed, May 7, 2014 at 9:13 PM, Marcus Ottosson <[email protected]>wrote: > >> > Pyparsing is defining a grammer. I haven't used it, but I can see >> where it would be useful when you have many rules that need to be >> considered. >> >> Ah, see, this is where I hesitate. If you've got that many rules to begin >> with, doesn't that mean you've quite reliant on strings for things that may >> be better suited for composition of objects, or a pre-defined schema for >> lists and the like? >> >> I'm eager to witness an example. >> >> >> On 7 May 2014 09:40, Stefan Andersson <[email protected]> wrote: >> >>> Thanks guys! >>> Lot's of information there! >>> >>> regards >>> stefan >>> >>> >>> >>> On Wed, May 7, 2014 at 9:38 AM, Justin Israel <[email protected]>wrote: >>> >>>> The re.compile() thing is a small optimization where you compile the >>>> pattern ahead of time so that it doesn't have to do it each time you reuse >>>> it. The re module actually caches the last 100 patterns anyways, so it only >>>> really matters if you have many regular expressions that you are using over >>>> and over again. >>>> >>>> >>>> On Wed, May 7, 2014 at 8:35 PM, Stefan Andersson >>>> <[email protected]>wrote: >>>> >>>>> Thanks! Though I can't get my head around those >>>>> >>>>> re.compile(r'\d+') >>>>> >>>>> >>>>> >>>>> >>>>> >>>>> >>>>> >>>>> On Wed, May 7, 2014 at 8:06 AM, Marcus Ottosson < >>>>> [email protected]> wrote: >>>>> >>>>>> Sorry, I completely missed the part of your questions containing the >>>>>> example. :) >>>>>> >>>>>> # 1. Get all string in a dict together with their version number >>>>>> pattern = re.compile(r'\d+') >>>>>> versions = {}for test in v: >>>>>> version = pattern.search(test).group() >>>>>> version = int(version) >>>>>> versions[version] = test >>>>>> # 2. Sort version numbers and fill up a new list of strings >>>>>> sorted_versions = []for version in sorted(versions): >>>>>> sorted_versions.append(versions[version]) >>>>>> print sorted_versions >>>>>> >>>>>> ['test_v1.ma', 'test_v2.ma' ...] >>>>>> >>>>>> >>>>>> >>>>>> On 7 May 2014 07:51, Marcus Ottosson <[email protected]> wrote: >>>>>> >>>>>>> You could do something like this: >>>>>>> >>>>>>> >>> version = re.search(r'v\d+.nk', 'my_nukeFile_v12.nk').group()>>> >>>>>>> >>> version'v12.nk' >>>>>>> >>>>>>> At this point, you are guaranteed to always have a ‘v’ infront, and >>>>>>> that it will always end with ‘.nk’. At which point you could >>>>>>> >>>>>>> >>> version = int(version[1:-3])12 >>>>>>> >>>>>>> >>>>>>> >>>>>>> On 7 May 2014 07:34, Stefan Andersson <[email protected]> wrote: >>>>>>> >>>>>>>> So here is a though. How would you guys go about to sort versioning >>>>>>>> that has no padding? For instance Nuke always adds v1,v2,v3 etc without >>>>>>>> padding. And some users are used to do that when versioning their >>>>>>>> files. I >>>>>>>> try and trap most of those things to add padding. But... there is >>>>>>>> always >>>>>>>> that case when you can't. >>>>>>>> >>>>>>>> v = ["test_v1.ma", "test_v2.ma","test_v11.ma","test_v8.ma"," >>>>>>>> test_v10.ma"] >>>>>>>> >>>>>>>> how would you sort and print the last version? In a clever way. >>>>>>>> Right now there is a lot of splitting and sorting for me to get it >>>>>>>> right. >>>>>>>> But it feels there would be a "smart" way with regex, but I can't get >>>>>>>> my >>>>>>>> head around how to use that. >>>>>>>> >>>>>>>> regards >>>>>>>> stefan >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> On Wed, May 7, 2014 at 6:42 AM, Marcus Ottosson < >>>>>>>> [email protected]> wrote: >>>>>>>> >>>>>>>>> Just reading up on Pyparsing so I could be off here, but I would >>>>>>>>> actually argue that if a codebase relies heavily enough on strings >>>>>>>>> (for >>>>>>>>> identification?) that regex no longer cuts it, I would consider >>>>>>>>> whether or >>>>>>>>> not there is a better way of doing it, and not necessarily turn to >>>>>>>>> heavier >>>>>>>>> guns in parsing. >>>>>>>>> >>>>>>>>> Again, I could very well be misunderstanding. Does anyone have an >>>>>>>>> example of Pyparsing in action? >>>>>>>>> >>>>>>>>> >>>>>>>>> On 7 May 2014 00:12, Jeremy YeoKhoo <[email protected]> wrote: >>>>>>>>> >>>>>>>>>> Thanks so much Chad, yes I agree. Not many TDs are aware or >>>>>>>>>> understand the necessity of good program design and structure (me >>>>>>>>>> included!) and in this case naming convention! Ill have to have a >>>>>>>>>> look at >>>>>>>>>> that and apply what I can to my own set of tools that i am currently >>>>>>>>>> in the >>>>>>>>>> process of creating >>>>>>>>>> >>>>>>>>>> Thanks >>>>>>>>>> -Jeremy >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> On Sunday, 4 May 2014 20:47:26 UTC+10, Jeremy YeoKhoo wrote: >>>>>>>>>> >>>>>>>>>>> Hey guys, >>>>>>>>>>> >>>>>>>>>>> This should be fairly easy for you guys who know regex. If I >>>>>>>>>>> have a string that I want to enable versioning, so say for an >>>>>>>>>>> example I >>>>>>>>>>> want to recognize a string if it contains ['v001', 'v002', etc...] >>>>>>>>>>> I have something like this... >>>>>>>>>>> >>>>>>>>>>> remp= re.search('[0-9]+', 'hello_v001') >>>>>>>>>>> print temp.group() >>>>>>>>>>> >>>>>>>>>>> but I dont want it to return when: >>>>>>>>>>> remp= re.search('[0-9]+', 'hello_001') >>>>>>>>>>> print temp.group() >>>>>>>>>>> >>>>>>>>>>> Thanks >>>>>>>>>>> -Jeremy >>>>>>>>>>> >>>>>>>>>>> -- >>>>>>>>>> You received this message because you are subscribed to the >>>>>>>>>> Google Groups "Python Programming for Autodesk Maya" group. >>>>>>>>>> To unsubscribe from this group and stop receiving emails from it, >>>>>>>>>> send an email to [email protected]. >>>>>>>>>> To view this discussion on the web visit >>>>>>>>>> https://groups.google.com/d/msgid/python_inside_maya/ba398c57-19f8-4096-8524-07f609f1496c%40googlegroups.com<https://groups.google.com/d/msgid/python_inside_maya/ba398c57-19f8-4096-8524-07f609f1496c%40googlegroups.com?utm_medium=email&utm_source=footer> >>>>>>>>>> . >>>>>>>>>> >>>>>>>>>> For more options, visit https://groups.google.com/d/optout. >>>>>>>>>> >>>>>>>>> >>>>>>>>> >>>>>>>>> >>>>>>>>> -- >>>>>>>>> *Marcus Ottosson* >>>>>>>>> [email protected] >>>>>>>>> >>>>>>>>> -- >>>>>>>>> You received this message because you are subscribed to the Google >>>>>>>>> Groups "Python Programming for Autodesk Maya" group. >>>>>>>>> To unsubscribe from this group and stop receiving emails from it, >>>>>>>>> send an email to [email protected]. >>>>>>>>> To view this discussion on the web visit >>>>>>>>> https://groups.google.com/d/msgid/python_inside_maya/CAFRtmOD-0rkPSh1QZrzntoLmk7Fawst3%3DGHWmT5w0Fo0yEgn5Q%40mail.gmail.com<https://groups.google.com/d/msgid/python_inside_maya/CAFRtmOD-0rkPSh1QZrzntoLmk7Fawst3%3DGHWmT5w0Fo0yEgn5Q%40mail.gmail.com?utm_medium=email&utm_source=footer> >>>>>>>>> . >>>>>>>>> >>>>>>>>> For more options, visit https://groups.google.com/d/optout. >>>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> -- >>>>>>>> Stefan Andersson | Digital Janitor >>>>>>>> social media -> "sanders3d" >>>>>>>> >>>>>>>> -- >>>>>>>> You received this message because you are subscribed to the Google >>>>>>>> Groups "Python Programming for Autodesk Maya" group. >>>>>>>> To unsubscribe from this group and stop receiving emails from it, >>>>>>>> send an email to [email protected]. >>>>>>>> To view this discussion on the web visit >>>>>>>> https://groups.google.com/d/msgid/python_inside_maya/CAKW24e29hZ%3DgrJndzhGxpw1j%2BEgVPc6Oi%2Bdcop5d_DMTwxtxCg%40mail.gmail.com<https://groups.google.com/d/msgid/python_inside_maya/CAKW24e29hZ%3DgrJndzhGxpw1j%2BEgVPc6Oi%2Bdcop5d_DMTwxtxCg%40mail.gmail.com?utm_medium=email&utm_source=footer> >>>>>>>> . >>>>>>>> >>>>>>>> For more options, visit https://groups.google.com/d/optout. >>>>>>>> >>>>>>> >>>>>>> >>>>>>> >>>>>>> -- >>>>>>> *Marcus Ottosson* >>>>>>> [email protected] >>>>>>> >>>>>> >>>>>> >>>>>> >>>>>> -- >>>>>> *Marcus Ottosson* >>>>>> [email protected] >>>>>> >>>>>> -- >>>>>> You received this message because you are subscribed to the Google >>>>>> Groups "Python Programming for Autodesk Maya" group. >>>>>> To unsubscribe from this group and stop receiving emails from it, >>>>>> send an email to [email protected]. >>>>>> To view this discussion on the web visit >>>>>> https://groups.google.com/d/msgid/python_inside_maya/CAFRtmOB1gRWVdmQW%3DpN83Th9tRfcgpquF135%2BnZw5uHf%3DFSN1g%40mail.gmail.com<https://groups.google.com/d/msgid/python_inside_maya/CAFRtmOB1gRWVdmQW%3DpN83Th9tRfcgpquF135%2BnZw5uHf%3DFSN1g%40mail.gmail.com?utm_medium=email&utm_source=footer> >>>>>> . >>>>>> >>>>>> For more options, visit https://groups.google.com/d/optout. >>>>>> >>>>> >>>>> >>>>> >>>>> -- >>>>> Stefan Andersson | Digital Janitor >>>>> social media -> "sanders3d" >>>>> >>>>> -- >>>>> You received this message because you are subscribed to the Google >>>>> Groups "Python Programming for Autodesk Maya" group. >>>>> To unsubscribe from this group and stop receiving emails from it, send >>>>> an email to [email protected]. >>>>> To view this discussion on the web visit >>>>> https://groups.google.com/d/msgid/python_inside_maya/CAKW24e3iNZDGBFTweCyBR%3DfYTFugtM%2BPYf9ZidDuHDDWM4Q-dQ%40mail.gmail.com<https://groups.google.com/d/msgid/python_inside_maya/CAKW24e3iNZDGBFTweCyBR%3DfYTFugtM%2BPYf9ZidDuHDDWM4Q-dQ%40mail.gmail.com?utm_medium=email&utm_source=footer> >>>>> . >>>>> >>>>> For more options, visit https://groups.google.com/d/optout. >>>>> >>>> >>>> -- >>>> You received this message because you are subscribed to the Google >>>> Groups "Python Programming for Autodesk Maya" group. >>>> To unsubscribe from this group and stop receiving emails from it, send >>>> an email to [email protected]. >>>> To view this discussion on the web visit >>>> https://groups.google.com/d/msgid/python_inside_maya/CAPGFgA0h9_C7qLE6iy%3DLXtm9U%2BjCRpFEzupFn2zPEG-8FxjO3w%40mail.gmail.com<https://groups.google.com/d/msgid/python_inside_maya/CAPGFgA0h9_C7qLE6iy%3DLXtm9U%2BjCRpFEzupFn2zPEG-8FxjO3w%40mail.gmail.com?utm_medium=email&utm_source=footer> >>>> . >>>> >>>> For more options, visit https://groups.google.com/d/optout. >>>> >>> >>> >>> >>> -- >>> Stefan Andersson | Digital Janitor >>> social media -> "sanders3d" >>> >>> -- >>> You received this message because you are subscribed to the Google >>> Groups "Python Programming for Autodesk Maya" group. >>> To unsubscribe from this group and stop receiving emails from it, send >>> an email to [email protected]. >>> To view this discussion on the web visit >>> https://groups.google.com/d/msgid/python_inside_maya/CAKW24e2TOXcVLf38S8ShKUGsZhZkrE0EWhqyewvLDUjoCKyJ_A%40mail.gmail.com<https://groups.google.com/d/msgid/python_inside_maya/CAKW24e2TOXcVLf38S8ShKUGsZhZkrE0EWhqyewvLDUjoCKyJ_A%40mail.gmail.com?utm_medium=email&utm_source=footer> >>> . >>> >>> For more options, visit https://groups.google.com/d/optout. >>> >> >> >> >> -- >> *Marcus Ottosson* >> [email protected] >> >> -- >> You received this message because you are subscribed to the Google Groups >> "Python Programming for Autodesk Maya" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to [email protected]. >> To view this discussion on the web visit >> https://groups.google.com/d/msgid/python_inside_maya/CAFRtmOD%3Dnvg0WiedApoPYVUoNoc7s6H3sVRn0wSw33_QPA%3DHVg%40mail.gmail.com<https://groups.google.com/d/msgid/python_inside_maya/CAFRtmOD%3Dnvg0WiedApoPYVUoNoc7s6H3sVRn0wSw33_QPA%3DHVg%40mail.gmail.com?utm_medium=email&utm_source=footer> >> . >> >> For more options, visit https://groups.google.com/d/optout. >> > > -- > You received this message because you are subscribed to the Google Groups > "Python Programming for Autodesk Maya" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To view this discussion on the web visit > https://groups.google.com/d/msgid/python_inside_maya/CAPGFgA2o4Zos4gsmmFWKZkNWs9N9OEAGNuZEh6e3OTMjH6HJ5w%40mail.gmail.com<https://groups.google.com/d/msgid/python_inside_maya/CAPGFgA2o4Zos4gsmmFWKZkNWs9N9OEAGNuZEh6e3OTMjH6HJ5w%40mail.gmail.com?utm_medium=email&utm_source=footer> > . > > For more options, visit https://groups.google.com/d/optout. > -- *Marcus Ottosson* [email protected] -- You received this message because you are subscribed to the Google Groups "Python Programming for Autodesk Maya" group. 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