:: Separator in class names

Hi,

due to the absence of a namespace solution we today often prefix classes with one, two or three letters.
You all know prefixes like "Zn", "Zdc", "GLM", "Tx", "WA", ... to avoid conflicting names.

I would like to have a "::" separator within the class name to better distinguish
the class name from the prefix and increase readability at the same time. SmalltalkMT
had this solution in alignment with C++ and I really liked working with it.
So much that I would like to see it in Pharo too - maybe also as a base for future Namespace
additions.

So I modified the #isValidGlobalName in Pharo 6.0 like mentioned below to allow and support
the :: notation for classes. After that I can create classes like:

  Seaside::Component
  Core::Boolean
  Model::Person
  GLM::BrickListModel
  Tx::FontAttribute

so far without any problem.

Do you think
 - there will be places where this conflicts or creates hazzles (tools, metacello, ...)
 - if it would be a good idea to add this to the default image?

Thanks for feedback.

Thx
T.

--------------------------------------------------------------------------------------------------
isValidGlobalName

        self ifEmpty: [ ^ false ].
       
        "reserverd default names"
        self = 'NameOfSubclass' ifTrue: [ ^ false ].
        self = 'TNameOfTrait' ifTrue: [ ^ false ].

        (self occurrencesOf: $:) = 2 ifTrue: [
                        ^(self splitOn: '::') allSatisfy: [: part | part isValidGlobalName ]
        ].

        ^ Character supportsNonASCII
                ifTrue: [
                        (self first isLetter
                                and: [self first isUppercase])
                                and: [ self allSatisfy: [:character |
                                                character isAlphaNumeric or: [ character = $_ ]]]]
                ifFalse: [
                        (self first between: $A and: $Z) and: [  
                                self allSatisfy: [:character |
                                        (character between: $a and: $z) or: [
                                        (character between: $A and: $Z) or: [
                                        (character between: $0 and: $9) or: [
                                        character = $_]]]]]]

Torsten,

Because of the obvious portability problems this would introduce, I
would think that an attempt should be made to come up with a common
namespace solution ...

I do believe that some discussion about namespace alternatives has taken
place between GemStone and Pharo --- not familiar with details or
outcome of discussions, but I would like to think that at least an
attempt was made to come up with a common solution before resorting to a
unilateral solution that would only introduce more isolation between the
various dialects --- something that a small community cannot really
afford to do ...

Dale

On 12/07/2016 04:47 PM, Torsten Bergmann wrote:

Aliaksei Syrel
>This thread has a huge discussion potential :)
 
Yes - I know it has :)

And it comes up from time to time ... mostly fading away.

Nonetheless I like to trigger it again. So far we have not made much progress
on that frontier and - even when we do not have a full, perfect or portable
namespace solution changing the current restriction what a "valid global name"
means (see method #isValidGlobalName) could help in exploring that area more
deeply.

Having at a minimum support for a scope like separator (I would suggest to use "::")
would allow to experiment with it from Pharo 6.0 onwards.  

>*grabs popcorn*

Why do you just want to be part of the audience
instead of telling us what you think?

Thanks
T.

Dale wrote:
>Because of the obvious portability problems this would introduce, I
>would think that an attempt should be made to come up with a common
>namespace solution ...

I'm not sure about the current namespace solutions existing today in vendor driven Smalltalks. You and me were participants in the first
CampSmalltalk in San Diego in 2000 with many others trying to get the Smalltalk's closer which was already hard at that time
because of the many dialects and differences (VW, VAST, Gemstone, Squeak, ST/MT, Dolphin, ...)

Some of this work influenced todays Smalltalk world with frameworks and tools. Today Smalltalks shares not only basic core classes
but also a common unit framework and similar test runners, have code exchange and formats, even a framework like Seaside could
somehow be managed "portable".

But there was not much success in REALLY aligning all the proprietary solutions regarding class libraries, common behavior of methods,
tools, UI or even frameworks. You cant file out, file in and just run.

Because we have different pragma solutions, different foreign function interfaces, different way of building tools ... even
differences on compiler and meta level. So "portability problems" are already a reality for many other reasons.

Dont get me wrong. I'm all ears if you see a way to build a "common" or "portable" route for unified namespace solution, but to make
this a reality:

 - commercial vendors would have to see a need for (another) portable solution
 - would need to invest into this topic with time and resources
 - would have to jump onto the "open" and MIT licensed bandwagon to share with open source Smalltalks like Squeak and Pharo
 - would have to adopt their own solutions to a new portable one
 - you would need to get all the different interests under one umbrella

Which I doubt such a thing will happen because vendors already have own proprietary existing namespace solutions. Even when this would
be possible they would have to invest in explaining this to their customers who also would need to migrate from existing vendor
namespace solutions.

This thread is not about Namespaces, just about an optional separator in global names. So independent from the reasons to start this thread  
I doubt we will ever find a path to a unified namespace solution. You can call me a pessimist in this regard, even in having a short-term
common namespace solution for Pharo, Squeak and Cuis.
 
>something that a small community cannot really afford to do

Community is not big ... but growing. At least from what I see in open source Smalltalks like Squeak, Pharo, Cuis, ... with new
community members, ideas, frameworks, books, unifying VM, ...

We would continue to be a small community if our world would have stopped and kept the things the way they were defined initially in ST.
I would not like to imagine the size of the overall ST community without the fresh air of these open source Smalltalks.

Maybe I'm mistaken but so far Pharo is already the one who EXPLORES new routes with Traits, Slots, MetaLinks, OpalCompiler, ...
often these are already "non-portable". So while you can use them if you are in need of them you should stay away from them
if you have portability to other Smalltalks in mind. Right?

This does not solve the portability issue but provides freedem: because you can share with other Smalltalks if necessary - but also
allows you to follow new paths, use slots and other.

But back to the topic:
======================
Please do not misunderstood my orginal post: I DONT want to have or discuss a new and perfect namespace solution now as an outcome
here. Usually when similar threads were discussed we only agreed that this never gets reality. ;)
 
I JUST want to change the single method #isValidGlobalName to be MORE FLEXIBLE and to allow for an EXPLICIT and OPTIONAL
SEPARATOR IN GLOBAL NAMES. Nothing less but also nothing more. So this is about an optional separator in global names, not
about a full namespace solution.

By allowing such a separator anyone (including me) who feels the need to experiment or try out new paths can then
play with it:

 - maybe just for readability to write prefixed classes like this "KillerApp::Window"
 - maybe just to avoid conflicts as with a better separated prefix ("MyKillApp::Person" vs. "YouKillerApp::Person")
 - maybe to experiment with having two versions of a class inside of the image "OldVersion::MyClass" and "NewVersion::MyClass"
 - maybe because you want to import/map namespace from other languages like Java/.NET/C++/... to it  
   (like mapping Java to Pharo as org::apache::commons::lang::StringUtils and so on) to experiment with Pharo as a
   multilanguage engine or experiment in a better JNIPort
 - maybe because you want to map different platform facilities or libraries ("Common::Window", "Windows::Window",
   "OSX::Window", "GTK::Window", ...)
 - maybe to provide useful shadow classes that are not visible by default in regular tools ("Shadows::Object", "Shadows::Boolean", ...)
 - maybe to be able to import and separate classes from different Smalltalk systems ("VW::Object", "VAST::Object", ...)
 - and yes: maybe also to do initial experiments towards a future portable or non-portable namespace solution
 - ...
 - [ADD YOUR OWN IDEAS HERE]


So anything I want is a single and small step forward: the possibility in Pharo 6 for global names to allow a
COMPLETELY OPTIONAL separator without having to "dirty patch" the method #isValidGlobalName in the base image.

So if one wants to write regular code or even portable code and code that is traditional, working with all tools
he could and should stay away from this OPTIONAL separator possibility. Nothing changes on the usual Pharo and Smalltalk side,
you can code and share as before.

But if one feels the need to use such a possibility for own custom stuff or experiments it is there and one can use it.
I feel a very strong need on my side for such experiments because I would like to explore new grounds with it. I can
patch/overwrite the method in my custom images - but this is not so clean and nice. Pharo should give this freedom out
of the box and I hope that you agree with me.

Maybe others have similar ideas and want to experiment as well. Thats why I opened this thread - if the community
supports the idea and shares similar visions I will open a bug, provide a slice and we include it. In my opinion it
opens new opportunities.

If community disagrees and it will not become part of the base image out of the box (or only as part of a full namespace solution)
I will continue patching my custom images. I'm fine with that as well - but then at least I tried to get this in.

Thanks
T.

Dale wrote:

Because of the obvious portability problems this would introduce, I 
would think that an attempt should be made to come up with a common 
namespace solution ...

I'm not sure about the current namespace solutions existing today in vendor driven Smalltalks. You and me were participants in the first 
CampSmalltalk in San Diego in 2000 with many others trying to get the Smalltalk's closer which was already hard at that time 
because of the many dialects and differences (VW, VAST, Gemstone, Squeak, ST/MT, Dolphin, ...) 

Some of this work influenced todays Smalltalk world with frameworks and tools. Today Smalltalks shares not only basic core classes
but also a common unit framework and similar test runners, have code exchange and formats, even a framework like Seaside could
somehow be managed "portable". 

But there was not much success in REALLY aligning all the proprietary solutions regarding class libraries, common behavior of methods,
tools, UI or even frameworks. You cant file out, file in and just run.

Because we have different pragma solutions, different foreign function interfaces, different way of building tools ... even 
differences on compiler and meta level. So "portability problems" are already a reality for many other reasons. 

Dont get me wrong. I'm all ears if you see a way to build a "common" or "portable" route for unified namespace solution, but to make 
this a reality: 

 - commercial vendors would have to see a need for (another) portable solution
 - would need to invest into this topic with time and resources
 - would have to jump onto the "open" and MIT licensed bandwagon to share with open source Smalltalks like Squeak and Pharo
 - would have to adopt their own solutions to a new portable one
 - you would need to get all the different interests under one umbrella 

Which I doubt such a thing will happen because vendors already have own proprietary existing namespace solutions. Even when this would 
be possible they would have to invest in explaining this to their customers who also would need to migrate from existing vendor 
namespace solutions.

Well I believe that GemStone is open to discussing and possibly implementing alternate non-proprietary namespace solutions and I can't speak for other vendors ...

This thread is not about Namespaces, just about an optional separator in global names. So independent from the reasons to start this thread  
I doubt we will ever find a path to a unified namespace solution. You can call me a pessimist in this regard, even in having a short-term
common namespace solution for Pharo, Squeak and Cuis.

... the question is not whether or not you are or are not a pessimist, but do you care about portability ... if you care then don't go off implementing language features that create portability headaches without giving other platforms a chance to participate in the solution

something that a small community cannot really afford to do

Community is not big ... but growing. At least from what I see in open source Smalltalks like Squeak, Pharo, Cuis, ... with new 
community members, ideas, frameworks, books, unifying VM, ...

And the problem that Smalltalk has had from almost the beginning of time and one that costs a lot of effort for all community members is that we do not have a common source code format and we do not have a "standard library definition". Developers in the ruby community do not spend any time at all porting frameworks from one ruby platform to another ruby platform and we Smalltalkers spend a significant amount of time porting packages between platforms and platform versions ...

Introducing additional incompatibilities without attempting to coordinate between platforms just creates a bigger burden.

We would continue to be a small community if our world would have stopped and kept the things the way they were defined initially in ST. 
I would not like to imagine the size of the overall ST community without the fresh air of these open source Smalltalks.

I don't believe that I'm saying "don't do this"...

Maybe I'm mistaken but so far Pharo is already the one who EXPLORES new routes with Traits, Slots, MetaLinks, OpalCompiler, ...
often these are already "non-portable". So while you can use them if you are in need of them you should stay away from them
if you have portability to other Smalltalks in mind. Right? 

Wrong ... I am not saying anything like that ..

Traits are something that we at GemStone have considered adding to our product ... but recently I recall Steph saying something to the effect of "Traits aren't worth doing" or something ... Now this could have been Steph just sounding off, but until that comment we were seriously considering adding Traits to GemStone 3.4 ... sadly it will not make it into 3.4 now ...

I have always been in favor of Pharo pushing the language forward, but when it comes to something fundamental like adding "namespace like features" to global names --- because it is easy to do ---

I pipe up and ask that a little bit more thought and cross platform discussion be put into th problm

This does not solve the portability issue but provides freedem: because you can share with other Smalltalks if necessary - but also 
allows you to follow new paths, use slots and other.

and in the spirit of sharing I think it is worth a discussion ...

But back to the topic:
======================
Please do not misunderstood my orginal post: I DONT want to have or discuss a new and perfect namespace solution now as an outcome 
here. Usually when similar threads were discussed we only agreed that this never gets reality. ;)
 
I JUST want to change the single method #isValidGlobalName to be MORE FLEXIBLE and to allow for an EXPLICIT and OPTIONAL
SEPARATOR IN GLOBAL NAMES. Nothing less but also nothing more. So this is about an optional separator in global names, not 
about a full namespace solution.

If these option features are not used, then we don't have a portability problem :)  I am not the namespace expert --- I do know that if Pharo introduces this option unilaterally and it is used, it will cause portability issues ....

By allowing such a separator anyone (including me) who feels the need to experiment or try out new paths can then 
play with it: 

 - maybe just for readability to write prefixed classes like this "KillerApp::Window"
 - maybe just to avoid conflicts as with a better separated prefix ("MyKillApp::Person" vs. "YouKillerApp::Person")
 - maybe to experiment with having two versions of a class inside of the image "OldVersion::MyClass" and "NewVersion::MyClass"
 - maybe because you want to import/map namespace from other languages like Java/.NET/C++/... to it  
   (like mapping Java to Pharo as org::apache::commons::lang::StringUtils and so on) to experiment with Pharo as a
   multilanguage engine or experiment in a better JNIPort 
 - maybe because you want to map different platform facilities or libraries ("Common::Window", "Windows::Window", 
   "OSX::Window", "GTK::Window", ...)
 - maybe to provide useful shadow classes that are not visible by default in regular tools ("Shadows::Object", "Shadows::Boolean", ...)
 - maybe to be able to import and separate classes from different Smalltalk systems ("VW::Object", "VAST::Object", ...)
 - and yes: maybe also to do initial experiments towards a future portable or non-portable namespace solution
 - ... 
 - [ADD YOUR OWN IDEAS HERE]

Frankly I am interested in hearing the opinions of the namespace experts on these ideas ...

So anything I want is a single and small step forward: the possibility in Pharo 6 for global names to allow a 
COMPLETELY OPTIONAL separator without having to "dirty patch" the method #isValidGlobalName in the base image. 

So if one wants to write regular code or even portable code and code that is traditional, working with all tools 
he could and should stay away from this OPTIONAL separator possibility. Nothing changes on the usual Pharo and Smalltalk side,
you can code and share as before.

But if one feels the need to use such a possibility for own custom stuff or experiments it is there and one can use it. 
I feel a very strong need on my side for such experiments because I would like to explore new grounds with it. I can 
patch/overwrite the method in my custom images - but this is not so clean and nice. Pharo should give this freedom out 
of the box and I hope that you agree with me. 

Maybe others have similar ideas and want to experiment as well. Thats why I opened this thread - if the community
supports the idea and shares similar visions I will open a bug, provide a slice and we include it. In my opinion it
opens new opportunities.

If community disagrees and it will not become part of the base image out of the box (or only as part of a full namespace solution)
I will continue patching my custom images. I'm fine with that as well - but then at least I tried to get this in.

Dale

First of all: happy new year to all Pharo supporters!

Not many of you answered this thread in 2016. Maybe
I have more luck in 2017 ;)

So please tell me about the requested change of #isValidGlobalName
to allow an optional separator in class names. I already communicated
possible usages and still do not share the fears of Dale that we
easily get unportable code with that. I guess it will allow us to
experiment much easier.

Thanks for taking the time to response and share your own thoughts!

Bye
Torsten

If we allow it now what would be the scenario rolling that back? Taking it away again seems to be much harder. My gut feeling tells me this would be a change we will regret later.

Norbert

> Thanks for taking the time to response and share your own thoughts!
>
> Bye
> Torsten
>
>

+100

I do not think that there should be restrictions on the number of :: separators.
Modified to allow #A::B::Object etc..
-------------------------------
isValidGlobalName

    self ifEmpty: [ ^ false ].
   
    "reserverd default names"
    self = #NameOfSubclass ifTrue: [ ^ false ].
    self = #TNameOfTrait ifTrue: [ ^ false ].

  (self splitOn: '::') allSatisfy: [: part |
                Character supportsNonASCII ifTrue: [
            (part first isLetter
                and: [ part first isUppercase])
                and: [ part allSatisfy: [:character |
                    character isAlphaNumeric or: [ character = $_ ]]]
        ]
        ifFalse: [
            (part first between: $A and: $Z) and: [  
                part allSatisfy: [:character |
                    (character between: $a and: $z) or: [
                        (character between: $A and: $Z) or: [
                        (character between: $0 and: $9) or: [
                         character = $_]]]]]
        ]
        ]
-------------------------------------

As long as the :: only serve as a visual separator between "namespace(s)" and class name then it should not be harder much more harder than to do a #copyReplaceAll: '::' with: '' when filing in|out the class to use in a system that do not allow :: in class names.

Best regards,
Henrik


-----Opprinnelig melding-----
Fra: Pharo-dev [mailto:[hidden email]] På vegne av Torsten Bergmann
Sendt: 02 January 2017 12:57
Til: Pharo Development List <[hidden email]>
Emne: Re: [Pharo-dev] :: Separator in class names

First of all: happy new year to all Pharo supporters!

Not many of you answered this thread in 2016. Maybe I have more luck in 2017 ;)

So please tell me about the requested change of #isValidGlobalName to allow an optional separator in class names. I already communicated possible usages and still do not share the fears of Dale that we easily get unportable code with that. I guess it will allow us to experiment much easier.

Thanks for taking the time to response and share your own thoughts!

Bye
Torsten

Hi all!

On 01/02/2017 02:16 PM, Henrik Nergaard wrote:
> +100
>
> I do not think that there should be restrictions on the number of :: separators.
> Modified to allow #A::B::Object etc..

Just wanted to mention that ... I am amused! :) My Namespace
implementation in Squeak from a bunch of years back used this notation.

And I am also using it in Spry, but as syntactic sugar for Dictionary
access so that:

        aDict at: #x

...can be expressed as:

        aDict::x

regards, Göran