Date: Sat, 16 Apr 2022 20:12:58 +0200
And .ixx is a decision I and programmers simply do not understand. It has nothing in common with .cpp. Nothing!
They wonder, what the problem with .cppm is, which at least is self explanatory and used by clang.
And wonder why gcc does not require a special suffix at all.
You should see the reaaction when I tell about .ixx using two 45 degree rotated +...
Folks, please do your job and let programmers chose their suffix and let compilers support whatever they choose.
Please!
Otherwise, the community is loosing faith for the standard committee.
For no good reason.
But I agree that this would not be a SG15 at all, if just Microsoft would be willig to let Visual C++ deal with any suffix.
The more I learn the less I understand why Microsoft is not willing to bring modules to life.
Sorry, tough words, I know.
But we all are soooo frustrated...
Am 16. April 2022 17:26:32 MESZ schrieb Bret Brown <mail_at_[hidden]>:
>That clarifies things for me, thanks.
>
>I recall consensus in a previous SG15 meeting to write up a report
>establishing ixx as the recommended suffix for module interface units. I
>haven't seen a draft of a report establishing that recommendation. Perhaps
>that was just a TODO that was overlooked and not followed up on.
>
>To be honest, these kinds of tasks are awkward for SG15 because there isn't
>an existing document to just enhance or amend.
>
>At any rate, I haven't seen any discussion about the need for different
>suffixes beyond ixx being worth converging on for interface units. This
>email thread is elucidating on the case for more convergence beyond ixx.
>
>If we're ready for concrete action, I believe we need a paper summarizing
>the concern and proposing the new extension(s). Assuming that is received
>well in SG-15, we also need someone to step up to draft a report about
>recommended naming for module source files.
>
>To restate earlier comments in this thread, I expect robust build systems
>like CMake and msbuild will need to be able to model unusual file
>extensions on a file by file granularity, so I don't expect this to
>simplify build systems much. Though perhaps it can help end users still.
>Build systems could pick sensible defaults the way CMake does now when
>given headers and source files in the same SOURCES list.
>
>Bret
>
>On Sat, Apr 16, 2022, 10:46 Nicolai Josuttis <nico_at_[hidden]> wrote:
>
>> Yes,
>>
>> for years for C++ programs we were able to say:
>>
>> g++ c1.cpp c2.cpp
>>
>> or
>>
>> cl c1.cpp c2.cpp
>>
>> we didn't have to care about details.
>>
>> Now with modules this simply doesn't work.
>> But it should and if it is only because programmers start with simple
>> examples (but they also use them for test code etc.).
>>
>> The status quo is that different compilers require different suffixes and
>> options and there are even worse restrictions.
>>
>> Given for example:
>>
>> mod3if.cpp : The module interface unit
>> mod3impl.cpp : An implementation unit
>> mod3part.cpp : An internal partition
>> mod3ifpart.cpp : An interface partition unit
>>
>> and to test this:
>>
>> mod3test.cpp : A traditional translation unit
>>
>> with gcc this works fine
>>
>> g++ mod3part.cpp mod3ifpart.cpp mod3if.cpp mod3impl.cpp mod3test.cpp
>>
>> With Visual C++ I cannot do compile all code together at all.
>> One reason is that Visual C++ does require /interface or
>> /internalPartition and does NOT allow both on one command line.
>>
>> I also cannot use other suffixes such as .ixx because compiler vendors
>> didn't agree on one.
>> Using .ixx means I have to use -xc++ (at least something I can do).
>> But even with that I cannot pass all files on ONE command line to cl.
>>
>> So for years I ask for a portable "hello modules" example. Tell me the
>> suffixes so that I can pass all files to the compiler and voila it runs. If
>> the suffix is .cpp OK, if it is .cppm fine, if it is .ixx (OK, although I
>> wonder why). For the community, this unfortunately looks like nobody is
>> interested to establish modules in practice.
>>
>> That frustrates me and that frustrates all programmers who want to use
>> modules.
>>
>> I agree that module shave other flaws yet and teach that. To be honest,
>> after showing the current pain to port even the simplest example understand
>> that for a different reason than Daniela points out.
>> They just wonder why we don't even enable a first working portable program.
>>
>> There is also no technical reason to provide portability.
>> Just fix the compilers (and/or ideally agree on suffixes) and we are one
>> important step forward.
>>
>> As promised I will ship today a script that fixes Visual C++ (at least for
>> simple cases).
>>
>> Calling:
>>
>> cl-fixed.py /std:c++latest mod3part.cpp mod3ifpart.cpp mod3if.cpp
>> mod3impl.cpp mod3test.cpp /Femod3.exe
>>
>> will automatically do the right thing:
>>
>> cl /std:c++latest /Femod3.exe /TP /c /internalPartition mod3part.cpp
>> cl /std:c++latest /Femod3.exe /TP /c /interface mod3ifpart.cpp
>> cl /std:c++latest /Femod3.exe /TP /c /interface mod3if.cpp
>> cl /std:c++latest /Femod3.exe /TP /c mod3impl.cpp
>> cl /std:c++latest /Femod3.exe /TP /c mod3test.cpp
>> cl /std:c++latest /Femod3.exe mod3part.obj mod3ifpart.obj mod3if.obj
>> mod3impl.obj mod3test.obj
>>
>> And of course you can use .ixx instead.
>>
>> Microsoft just would have to put that into Visual Studio. I hope they do.
>>
>> Does this explanation help?
>>
>> Best
>>
>> Nico
>>
>>
>> Am 16.04.2022 um 14:44 schrieb Bret Brown:
>>
>>
>> Of course for programmers a portable program implies that
>> a) I don't have to rename files
>> b) I don't have to use different conmand-line options for files having the
>> same suffix
>> c) I can compile all code with a single command
>>
>> If we expect C++ engineers to fiddle with command-line options or
>> hand-roll compile commands, modules aren't ready yet. On all toolchains,
>> those compile options would need to indicate, one way or another, all of
>> the transitive modular dependencies to parse. And for each of those
>> dependencies, we would need metadata sufficient to parse them with *their* chosen
>> flags to avoid ODR violations. We don't have enough convergence to make it
>> feasible to portably maintain that logic in version-controlled build system
>> configuration files.
>>
>> To address that problem, SG-15 has been trying to converge on a "library"
>> as being the primary dependency declaration mechanism for the end user and
>> for relevant metadata files. If that's possible, a lot of the things in
>> this thread become simpler -- the library would come with metadata
>> indicating the categories and purposes of various files. Link lines are
>> already concepts modeled by build systems and they could be leveraged to
>> discover that library metadata. The build system would be enhanced to turn
>> library names from a link line into appropriate compile commands.
>>
>> Given that, I expect engineers will maintain lists of direct
>> library dependencies for their build systems. I don't expect engineers will
>> hand-roll entire compile commands for every transitive dependency to
>> version control and commit them. *If hand-rolling compile commands is a
>> must-have, we have even more work to do, so please come forward with use
>> cases.*
>>
>> At any rate, I wouldn't bother teaching the C++ community how to construct
>> compile commands. That activity would mostly be for researchers, toolchain
>> maintainers, build system engineers, etc. I expect the in-the-trenches C++
>> engineer would instead be referred to the documentation for the build
>> system of choice, especially the portion about how to declare dependencies.
>>
>> I realize that many engineers don't have robust build system documentation
>> to refer to because they use some sort of bespoke build system. But I
>> expect bespoke build systems (like hand-rolled Makefile) to clash with
>> modular projects and modular dependencies. If that's a concern, I encourage
>> relevant folks to invest in tools analogous to pkg-config so that bespoke
>> build systems as a group can be supported. Bloomberg provided a (now
>> slightly out-of-date) proof-of-concept for that approach here:
>> https://github.com/bloomberg/p2473. It has a utility to generate compile
>> command fragments from metadata. It has another utility to generate compile
>> commands for transitive dependencies for incorporation into the build rules
>> graph.
>>
>>
>> Once we have that, we can teach content and programmers will use it. So
>> far, the clear conclusion is that you cannot use modules in practice.
>>
>>
>> I can't use standard modules in practice, no. *I think the C++ community
>> is overestimating how ready modules are for practical use. *Even if all
>> of MSVC, Clang, and GCC were feature-complete and had analogous (if
>> differently-spelled) compile options, I don't think building modular
>> projects portably would be feasible. Possibly it could be doable if all
>> dependencies were vendored into one big repository and all source code in
>> that repository shared the same, modules-capable build system. I haven't
>> heard of any organization doing that successfully yet, not with standard
>> C++ modules, but I'm interested in learning from others' experiences if
>> anyone can share.
>>
>> Bret
>>
>> On Sat, Apr 16, 2022 at 2:42 AM Nico Josuttis via SG15 <
>> sg15_at_[hidden]> wrote:
>>
>>> Gaby,
>>>
>>> you want me to tell programmers that we have portable examples, for which
>>> unfortunately there is not defined HOW to deal with them?
>>> And selling this as "you can use modules in practice"? đ¤
>>>
>>> Of course for programmers a portable program implies that
>>> a) I don't have to rename files
>>> b) I don't have to use different conmand-line options for files having
>>> the same suffix
>>> c) I can compile all code with a single command
>>>
>>> Once we have that, we can teach content and programmers will use it. So
>>> far, the clear conclusion is that you cannot use modules in practice.
>>>
>>> It would be absolutely no problem to provide that for Visual C++.
>>> Ideally ignoring file extensions and analyze C++ file content.
>>> Therefore, I wonder why you do not WANT that (and at the same time tell
>>> that you are interesting that modules become widely used).
>>>
>>> And, BTW, I am desperately looking for the file extension Visual C++
>>> expect for internal patition units
>>> (to skip /internalPartition).
>>> PLEASE just tell us.
>>>
>>> Thanks
>>>
>>>
>>>
>>> Am 15. April 2022 21:46:13 MESZ schrieb Gabriel Dos Reis <
>>> gdr_at_[hidden]>:
>>> >Fortunately, there IS a portable C++ example of âhello worldâ program,
>>> today.
>>> >
>>> >*How* to compile a given source file has always depended on compilers,
>>> their environment of invocations, and supporting toolsets. That wonât
>>> change. And Modules donât have a goal of changing that.
>>> >
>>> >Requiring that the set of satellite files that a compiler has to produce
>>> depends solely on the contents of the source file, and not on the
>>> invocation command lines, isnât going to work in real world, production
>>> environments. That is what build systems are for, to abstract over the
>>> details. My hope is that professional teaching of programming with
>>> modules direct C++ programmers to relying on their build systems.
>>> >
>>> >We are having a conversation in SG15 about common ways of describing to
>>> build systems what are the needs of a program and library, and let the
>>> build system make the build happens. And that is not restricted to
>>> modules, even though they make the conversation urgent.
>>> >
>>> >-- Gaby
>>> >
>>> >From: Nico Josuttis <nico_at_[hidden]>
>>> >Sent: Friday, April 15, 2022 12:05 PM
>>> >To: ext_at_[hidden]; Gabriel Dos Reis via Ext <ext_at_[hidden]>;
>>> ext_at_[hidden]; sg15_at_[hidden]
>>> >Cc: Gabriel Dos Reis <gdr_at_[hidden]>; Nathan Sidwell <nathan_at_[hidden]
>>> >
>>> >Subject: Re: [isocpp-ext] [SG15] Can we expect that all C++ source files
>>> can have the same suffix?
>>> >
>>> >haha,
>>> >I REALLY would like to have the first portable "hello module" example.
>>> >
>>> >Currently, there is simply no way to have it. That's really a shame.
>>> >
>>> >
>>> >Am 15. April 2022 20:46:59 MESZ schrieb Gabriel Dos Reis via Ext <
>>> ext_at_[hidden]<mailto:ext_at_[hidden]>>:
>>> >
>>> >Nathan - you recount is all correct.
>>> >
>>> >I know I've mentioned it more than once, but I find it unsettling, given
>>> there
>>> >was great opposition to there being a (two way?) mapping between file
>>> names and
>>> >module names, that there is a move in the direction of making file names
>>> >'significant'. ISTM that the desire for bob.$REGULARSUFFIX and
>>> >alice.$MODULESUFFIX is taking us all the way back to the first objection
>>> above
>>> >about having two languages.
>>> >
>>> >I am not seeing any movement to make filename suffixes significant in
>>> the linguistic interpretation, by the compiler, of the content of source
>>> file. Maybe I am not looking right; but I would definitely recommend
>>> against such move. There are extra linguistic considerations that might
>>> force a toolset (not just a compiler) to require certain suffixes, but
>>> those suffixes do not determine the meaning a C++ program -- this is not
>>> different from compilers like GCC or MSVC refusing to compile in default
>>> mode files ending with ".h" or similar because they generally have other
>>> connotations.
>>> >
>>> >For some reasons, the topic of the "right" suffix seems to generate more
>>> passion than the topic of what can we do with modules, so maybe we are
>>> already doing a lot with modules đ
>>> >
>>> >-- Gaby
>>> >
>>> >-----Original Message-----
>>> >From: Ext <ext-bounces_at_[hidden]<mailto:
>>> ext-bounces_at_[hidden]>> On Behalf Of Nathan Sidwell via Ext
>>> >Sent: Friday, April 15, 2022 11:21 AM
>>> >To: sg15_at_[hidden]<mailto:sg15_at_[hidden]>;
>>> ext_at_[hidden]<mailto:ext_at_[hidden]>; WG21 Tooling Study
>>> Group SG15 <tooling_at_[hidden]<mailto:tooling_at_[hidden]>>
>>> >Cc: Nathan Sidwell <nathan_at_[hidden]<mailto:nathan_at_[hidden]>>
>>> >Subject: Re: [isocpp-ext] [SG15] Can we expect that all C++ source files
>>> can have the same suffix?
>>> >
>>> >On 4/13/22 17:10, Nico Josuttis via SG15 wrote:
>>> >
>>> >I should add that the fact that we need
>>> >module;
>>> >at the beginning of the global module fragment was only introduced to
>>> let a file
>>> >identify itself as module file.
>>> >If we would require different suffixes, that would not have been
>>> necessary.
>>> >
>>> >But correct me if I am wrong.
>>> >
>>> >I shall correct you :)
>>> >
>>> >Here's the history (as I recall, all persons mentioned are real, and not
>>> to be
>>> >confused with ficticious characters)
>>> >
>>> >* prior to me doing things with gcc, there was only 'module FOO;' as a
>>> module
>>> >declaration at-most once within a TU. MSVC (the only compiler with
>>> module
>>> >smarts at the time), had a flag to tell it 'this is an interface' vs
>>> 'this is an
>>> >implementation'.
>>> >
>>> >* I found this unsatisfying, as it meant that there was something
>>> outside the
>>> >source tokens that told you how to interpret them. In effect we had two
>>> languages.
>>> >
>>> >* IIRC, Gaby, Jason (Merrill) and I came up with the 'export module
>>> FOO;' vs
>>> >'module foo;' distinction. But still this could be anywhere in the
>>> source
>>> >stream. I was able to implement this functionality to a working system.
>>> >
>>> >* Daveed proposed an early signifier of 'hey, this is gonna be a
>>> module', should
>>> >the actual module declaration not be first. Hence 'module;' was born.
>>> (My
>>> >understanding was that this was driven by implementors, as they had
>>> difficulty
>>> >entering a module-like mode not at start of compilation, and indeed it
>>> was a
>>> >little tricky to do that. I do not know if this was also a user request.)
>>> >
>>> >* post p1103, the requirement that everything between 'module;' and the
>>> module
>>> >decl come from #include came to be.
>>> >
>>> >Hope that helps.
>>> >
>>> >I know I've mentioned it more than once, but I find it unsettling, given
>>> there
>>> >was great opposition to there being a (two way?) mapping between file
>>> names and
>>> >module names, that there is a move in the direction of making file names
>>> >'significant'. ISTM that the desire for bob.$REGULARSUFFIX and
>>> >alice.$MODULESUFFIX is taking us all the way back to the first objection
>>> above
>>> >about having two languages.
>>> >
>>> >nathan
>>> >
>>> >
>>> >
>>> >Am 13. April 2022 22:58:13 MESZ schrieb Nicolai Josuttis via Ext
>>> ><ext_at_[hidden]<mailto:ext_at_[hidden]>>:
>>> >
>>> > What I teach about modules is compelling. Programmers like and want
>>> to use it.
>>> > However, they ask how they should organize module files in practice.
>>> >
>>> > So far I cannot recommend a specific suffix (and I might never be
>>> able to do
>>> > that).
>>> > However there is one important question that IMO the standard should
>>> answer:
>>> > *Do we **/need /**different suffixes?*
>>> >
>>> > I understand that a suffix discussion is only of practical value.
>>> > But IMO the standard has to give an answer here (which has nothing
>>> to do
>>> > with which suffixes are used).
>>> >
>>> > Let me elaborate that in detail:
>>> >
>>> > Not having a standard suffix has interesting consequences.
>>> > So far we have header files and translation units.
>>> > But once we know what a C++ translation unit is, we can just compile
>>> them
>>> > all with the same compiler options or commands. Because in practice
>>> we have
>>> > different suffixes for header and source files, we can set-up
>>> generic rules
>>> > to compile our code.
>>> >
>>> > This works for any suffix, provided you know the way to tell the
>>> compiler
>>> > that we have a C++ file here:
>>> > (use /Tp with VC++ and -xc++ with gcc and you are done).
>>> >
>>> > Is this still true with modules?
>>> > That is: Can we expect that identifying a file as C++ file is enough
>>> to be
>>> > able to (pre) compile it as C++ file?
>>> >
>>> > Current compilers give different answers (AFAIK):
>>> >
>>> > - *gcc *says the same suffix is possible. There is not special
>>> option for
>>> > modules.
>>> > I can still have my own suffixes and use -xc++ though.
>>> >
>>> > - *VC++* currently requires different suffixes or different
>>> command-line
>>> > arguments.
>>> > Identifying a file as C++ file is not enough.
>>> > For example
>>> > - This is not enough: /Tp mymod.cppm
>>> > - You need: /interface /Tp mymod.cppm
>>> >
>>> > I wonder whether the behavior of VC++ is standard conforming.
>>> >
>>> > I see no place in the C++ standard saying that there has to be
>>> different
>>> > treatment of C++ source files to make them work.
>>> > Or do we require this somewhere?
>>> > We do not require different treatment just because we have templates,
>>> > namespaces, or exceptions used inside.
>>> > Therefore, I would expect that also using modules does not require
>>> special
>>> > handling.
>>> > (This is independent from the question whether different suffixes
>>> help to
>>> > deal with these files).
>>> >
>>> > If I am right, VC++ is not standard conforming.
>>> >
>>> >
>>> > In any case it would help a lot to clarify:
>>> > Can all C++ source files expect that treating them the same way
>>> works fine?
>>> >
>>> > If not, we obviously need different suffixes. But then we should
>>> clearly say
>>> > so (without necessarily saying which suffix it is).
>>> >
>>> >
>>> > I hope this questions brings us a bit forward to be able teach the
>>> first
>>> > *portable *"hello, modules" example.
>>> >
>>> > Thanks
>>> >
>>> > Nico
>>> >
>>> > --
>>> >
>>> >________________________________
>>> >
>>> > Nicolai M. Josuttis
>>> >
>>> https://nam06.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.josuttis.de%2F&data=05%7C01%7Cgdr%40microsoft.com%7Cbd5d9b59ad484906820b08da1f0cac6f%7C72f988bf86f141af91ab2d7cd011db47%7C1%7C0%7C637856436548406876%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=rGQUFYPVGC6vH5MaGf4q6GG%2BB8fTzeWGtqy%2BSjZ9w30%3D&reserved=0
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>>> >
>>> > +49 (0)531 / 129 88 86
>>> > +49 (0)700 / JOSUTTIS
>>> >
>>> > Books:
>>> > C++:
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>>> ,
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>>> >
>>> >
>>> >--
>>> >Nico Josuttis
>>> >(sent from my mobile phone)
>>> >
>>> >________________________________
>>> >
>>> >SG15 mailing list
>>> >SG15_at_[hidden]<mailto:SG15_at_[hidden]>
>>> >
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>>> >
>>> >
>>> >
>>> >
>>> >--
>>> >Nathan Sidwell
>>> >
>>> >________________________________
>>> >
>>> >Ext mailing list
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>>> >--
>>> >Nico Josuttis
>>> >(sent from my mobile phone)
>>>
>>> --
>>> Nico Josuttis
>>> (sent from my mobile phone)
>>> _______________________________________________
>>> SG15 mailing list
>>> SG15_at_[hidden]
>>> https://lists.isocpp.org/mailman/listinfo.cgi/sg15
>>>
>> --
>> ---
>> Nicolai M. Josuttiswww.josuttis.de
>> +49 (0)531 / 129 88 86
>> +49 (0)700 / JOSUTTIS
>>
>> Books:
>> C++: http://cppstd20.com, http://cppstd17.com, http://cppmove.com,
>> http://cppstdlib.com, http://tmplbook.com
>>
>>
They wonder, what the problem with .cppm is, which at least is self explanatory and used by clang.
And wonder why gcc does not require a special suffix at all.
You should see the reaaction when I tell about .ixx using two 45 degree rotated +...
Folks, please do your job and let programmers chose their suffix and let compilers support whatever they choose.
Please!
Otherwise, the community is loosing faith for the standard committee.
For no good reason.
But I agree that this would not be a SG15 at all, if just Microsoft would be willig to let Visual C++ deal with any suffix.
The more I learn the less I understand why Microsoft is not willing to bring modules to life.
Sorry, tough words, I know.
But we all are soooo frustrated...
Am 16. April 2022 17:26:32 MESZ schrieb Bret Brown <mail_at_[hidden]>:
>That clarifies things for me, thanks.
>
>I recall consensus in a previous SG15 meeting to write up a report
>establishing ixx as the recommended suffix for module interface units. I
>haven't seen a draft of a report establishing that recommendation. Perhaps
>that was just a TODO that was overlooked and not followed up on.
>
>To be honest, these kinds of tasks are awkward for SG15 because there isn't
>an existing document to just enhance or amend.
>
>At any rate, I haven't seen any discussion about the need for different
>suffixes beyond ixx being worth converging on for interface units. This
>email thread is elucidating on the case for more convergence beyond ixx.
>
>If we're ready for concrete action, I believe we need a paper summarizing
>the concern and proposing the new extension(s). Assuming that is received
>well in SG-15, we also need someone to step up to draft a report about
>recommended naming for module source files.
>
>To restate earlier comments in this thread, I expect robust build systems
>like CMake and msbuild will need to be able to model unusual file
>extensions on a file by file granularity, so I don't expect this to
>simplify build systems much. Though perhaps it can help end users still.
>Build systems could pick sensible defaults the way CMake does now when
>given headers and source files in the same SOURCES list.
>
>Bret
>
>On Sat, Apr 16, 2022, 10:46 Nicolai Josuttis <nico_at_[hidden]> wrote:
>
>> Yes,
>>
>> for years for C++ programs we were able to say:
>>
>> g++ c1.cpp c2.cpp
>>
>> or
>>
>> cl c1.cpp c2.cpp
>>
>> we didn't have to care about details.
>>
>> Now with modules this simply doesn't work.
>> But it should and if it is only because programmers start with simple
>> examples (but they also use them for test code etc.).
>>
>> The status quo is that different compilers require different suffixes and
>> options and there are even worse restrictions.
>>
>> Given for example:
>>
>> mod3if.cpp : The module interface unit
>> mod3impl.cpp : An implementation unit
>> mod3part.cpp : An internal partition
>> mod3ifpart.cpp : An interface partition unit
>>
>> and to test this:
>>
>> mod3test.cpp : A traditional translation unit
>>
>> with gcc this works fine
>>
>> g++ mod3part.cpp mod3ifpart.cpp mod3if.cpp mod3impl.cpp mod3test.cpp
>>
>> With Visual C++ I cannot do compile all code together at all.
>> One reason is that Visual C++ does require /interface or
>> /internalPartition and does NOT allow both on one command line.
>>
>> I also cannot use other suffixes such as .ixx because compiler vendors
>> didn't agree on one.
>> Using .ixx means I have to use -xc++ (at least something I can do).
>> But even with that I cannot pass all files on ONE command line to cl.
>>
>> So for years I ask for a portable "hello modules" example. Tell me the
>> suffixes so that I can pass all files to the compiler and voila it runs. If
>> the suffix is .cpp OK, if it is .cppm fine, if it is .ixx (OK, although I
>> wonder why). For the community, this unfortunately looks like nobody is
>> interested to establish modules in practice.
>>
>> That frustrates me and that frustrates all programmers who want to use
>> modules.
>>
>> I agree that module shave other flaws yet and teach that. To be honest,
>> after showing the current pain to port even the simplest example understand
>> that for a different reason than Daniela points out.
>> They just wonder why we don't even enable a first working portable program.
>>
>> There is also no technical reason to provide portability.
>> Just fix the compilers (and/or ideally agree on suffixes) and we are one
>> important step forward.
>>
>> As promised I will ship today a script that fixes Visual C++ (at least for
>> simple cases).
>>
>> Calling:
>>
>> cl-fixed.py /std:c++latest mod3part.cpp mod3ifpart.cpp mod3if.cpp
>> mod3impl.cpp mod3test.cpp /Femod3.exe
>>
>> will automatically do the right thing:
>>
>> cl /std:c++latest /Femod3.exe /TP /c /internalPartition mod3part.cpp
>> cl /std:c++latest /Femod3.exe /TP /c /interface mod3ifpart.cpp
>> cl /std:c++latest /Femod3.exe /TP /c /interface mod3if.cpp
>> cl /std:c++latest /Femod3.exe /TP /c mod3impl.cpp
>> cl /std:c++latest /Femod3.exe /TP /c mod3test.cpp
>> cl /std:c++latest /Femod3.exe mod3part.obj mod3ifpart.obj mod3if.obj
>> mod3impl.obj mod3test.obj
>>
>> And of course you can use .ixx instead.
>>
>> Microsoft just would have to put that into Visual Studio. I hope they do.
>>
>> Does this explanation help?
>>
>> Best
>>
>> Nico
>>
>>
>> Am 16.04.2022 um 14:44 schrieb Bret Brown:
>>
>>
>> Of course for programmers a portable program implies that
>> a) I don't have to rename files
>> b) I don't have to use different conmand-line options for files having the
>> same suffix
>> c) I can compile all code with a single command
>>
>> If we expect C++ engineers to fiddle with command-line options or
>> hand-roll compile commands, modules aren't ready yet. On all toolchains,
>> those compile options would need to indicate, one way or another, all of
>> the transitive modular dependencies to parse. And for each of those
>> dependencies, we would need metadata sufficient to parse them with *their* chosen
>> flags to avoid ODR violations. We don't have enough convergence to make it
>> feasible to portably maintain that logic in version-controlled build system
>> configuration files.
>>
>> To address that problem, SG-15 has been trying to converge on a "library"
>> as being the primary dependency declaration mechanism for the end user and
>> for relevant metadata files. If that's possible, a lot of the things in
>> this thread become simpler -- the library would come with metadata
>> indicating the categories and purposes of various files. Link lines are
>> already concepts modeled by build systems and they could be leveraged to
>> discover that library metadata. The build system would be enhanced to turn
>> library names from a link line into appropriate compile commands.
>>
>> Given that, I expect engineers will maintain lists of direct
>> library dependencies for their build systems. I don't expect engineers will
>> hand-roll entire compile commands for every transitive dependency to
>> version control and commit them. *If hand-rolling compile commands is a
>> must-have, we have even more work to do, so please come forward with use
>> cases.*
>>
>> At any rate, I wouldn't bother teaching the C++ community how to construct
>> compile commands. That activity would mostly be for researchers, toolchain
>> maintainers, build system engineers, etc. I expect the in-the-trenches C++
>> engineer would instead be referred to the documentation for the build
>> system of choice, especially the portion about how to declare dependencies.
>>
>> I realize that many engineers don't have robust build system documentation
>> to refer to because they use some sort of bespoke build system. But I
>> expect bespoke build systems (like hand-rolled Makefile) to clash with
>> modular projects and modular dependencies. If that's a concern, I encourage
>> relevant folks to invest in tools analogous to pkg-config so that bespoke
>> build systems as a group can be supported. Bloomberg provided a (now
>> slightly out-of-date) proof-of-concept for that approach here:
>> https://github.com/bloomberg/p2473. It has a utility to generate compile
>> command fragments from metadata. It has another utility to generate compile
>> commands for transitive dependencies for incorporation into the build rules
>> graph.
>>
>>
>> Once we have that, we can teach content and programmers will use it. So
>> far, the clear conclusion is that you cannot use modules in practice.
>>
>>
>> I can't use standard modules in practice, no. *I think the C++ community
>> is overestimating how ready modules are for practical use. *Even if all
>> of MSVC, Clang, and GCC were feature-complete and had analogous (if
>> differently-spelled) compile options, I don't think building modular
>> projects portably would be feasible. Possibly it could be doable if all
>> dependencies were vendored into one big repository and all source code in
>> that repository shared the same, modules-capable build system. I haven't
>> heard of any organization doing that successfully yet, not with standard
>> C++ modules, but I'm interested in learning from others' experiences if
>> anyone can share.
>>
>> Bret
>>
>> On Sat, Apr 16, 2022 at 2:42 AM Nico Josuttis via SG15 <
>> sg15_at_[hidden]> wrote:
>>
>>> Gaby,
>>>
>>> you want me to tell programmers that we have portable examples, for which
>>> unfortunately there is not defined HOW to deal with them?
>>> And selling this as "you can use modules in practice"? đ¤
>>>
>>> Of course for programmers a portable program implies that
>>> a) I don't have to rename files
>>> b) I don't have to use different conmand-line options for files having
>>> the same suffix
>>> c) I can compile all code with a single command
>>>
>>> Once we have that, we can teach content and programmers will use it. So
>>> far, the clear conclusion is that you cannot use modules in practice.
>>>
>>> It would be absolutely no problem to provide that for Visual C++.
>>> Ideally ignoring file extensions and analyze C++ file content.
>>> Therefore, I wonder why you do not WANT that (and at the same time tell
>>> that you are interesting that modules become widely used).
>>>
>>> And, BTW, I am desperately looking for the file extension Visual C++
>>> expect for internal patition units
>>> (to skip /internalPartition).
>>> PLEASE just tell us.
>>>
>>> Thanks
>>>
>>>
>>>
>>> Am 15. April 2022 21:46:13 MESZ schrieb Gabriel Dos Reis <
>>> gdr_at_[hidden]>:
>>> >Fortunately, there IS a portable C++ example of âhello worldâ program,
>>> today.
>>> >
>>> >*How* to compile a given source file has always depended on compilers,
>>> their environment of invocations, and supporting toolsets. That wonât
>>> change. And Modules donât have a goal of changing that.
>>> >
>>> >Requiring that the set of satellite files that a compiler has to produce
>>> depends solely on the contents of the source file, and not on the
>>> invocation command lines, isnât going to work in real world, production
>>> environments. That is what build systems are for, to abstract over the
>>> details. My hope is that professional teaching of programming with
>>> modules direct C++ programmers to relying on their build systems.
>>> >
>>> >We are having a conversation in SG15 about common ways of describing to
>>> build systems what are the needs of a program and library, and let the
>>> build system make the build happens. And that is not restricted to
>>> modules, even though they make the conversation urgent.
>>> >
>>> >-- Gaby
>>> >
>>> >From: Nico Josuttis <nico_at_[hidden]>
>>> >Sent: Friday, April 15, 2022 12:05 PM
>>> >To: ext_at_[hidden]; Gabriel Dos Reis via Ext <ext_at_[hidden]>;
>>> ext_at_[hidden]; sg15_at_[hidden]
>>> >Cc: Gabriel Dos Reis <gdr_at_[hidden]>; Nathan Sidwell <nathan_at_[hidden]
>>> >
>>> >Subject: Re: [isocpp-ext] [SG15] Can we expect that all C++ source files
>>> can have the same suffix?
>>> >
>>> >haha,
>>> >I REALLY would like to have the first portable "hello module" example.
>>> >
>>> >Currently, there is simply no way to have it. That's really a shame.
>>> >
>>> >
>>> >Am 15. April 2022 20:46:59 MESZ schrieb Gabriel Dos Reis via Ext <
>>> ext_at_[hidden]<mailto:ext_at_[hidden]>>:
>>> >
>>> >Nathan - you recount is all correct.
>>> >
>>> >I know I've mentioned it more than once, but I find it unsettling, given
>>> there
>>> >was great opposition to there being a (two way?) mapping between file
>>> names and
>>> >module names, that there is a move in the direction of making file names
>>> >'significant'. ISTM that the desire for bob.$REGULARSUFFIX and
>>> >alice.$MODULESUFFIX is taking us all the way back to the first objection
>>> above
>>> >about having two languages.
>>> >
>>> >I am not seeing any movement to make filename suffixes significant in
>>> the linguistic interpretation, by the compiler, of the content of source
>>> file. Maybe I am not looking right; but I would definitely recommend
>>> against such move. There are extra linguistic considerations that might
>>> force a toolset (not just a compiler) to require certain suffixes, but
>>> those suffixes do not determine the meaning a C++ program -- this is not
>>> different from compilers like GCC or MSVC refusing to compile in default
>>> mode files ending with ".h" or similar because they generally have other
>>> connotations.
>>> >
>>> >For some reasons, the topic of the "right" suffix seems to generate more
>>> passion than the topic of what can we do with modules, so maybe we are
>>> already doing a lot with modules đ
>>> >
>>> >-- Gaby
>>> >
>>> >-----Original Message-----
>>> >From: Ext <ext-bounces_at_[hidden]<mailto:
>>> ext-bounces_at_[hidden]>> On Behalf Of Nathan Sidwell via Ext
>>> >Sent: Friday, April 15, 2022 11:21 AM
>>> >To: sg15_at_[hidden]<mailto:sg15_at_[hidden]>;
>>> ext_at_[hidden]<mailto:ext_at_[hidden]>; WG21 Tooling Study
>>> Group SG15 <tooling_at_[hidden]<mailto:tooling_at_[hidden]>>
>>> >Cc: Nathan Sidwell <nathan_at_[hidden]<mailto:nathan_at_[hidden]>>
>>> >Subject: Re: [isocpp-ext] [SG15] Can we expect that all C++ source files
>>> can have the same suffix?
>>> >
>>> >On 4/13/22 17:10, Nico Josuttis via SG15 wrote:
>>> >
>>> >I should add that the fact that we need
>>> >module;
>>> >at the beginning of the global module fragment was only introduced to
>>> let a file
>>> >identify itself as module file.
>>> >If we would require different suffixes, that would not have been
>>> necessary.
>>> >
>>> >But correct me if I am wrong.
>>> >
>>> >I shall correct you :)
>>> >
>>> >Here's the history (as I recall, all persons mentioned are real, and not
>>> to be
>>> >confused with ficticious characters)
>>> >
>>> >* prior to me doing things with gcc, there was only 'module FOO;' as a
>>> module
>>> >declaration at-most once within a TU. MSVC (the only compiler with
>>> module
>>> >smarts at the time), had a flag to tell it 'this is an interface' vs
>>> 'this is an
>>> >implementation'.
>>> >
>>> >* I found this unsatisfying, as it meant that there was something
>>> outside the
>>> >source tokens that told you how to interpret them. In effect we had two
>>> languages.
>>> >
>>> >* IIRC, Gaby, Jason (Merrill) and I came up with the 'export module
>>> FOO;' vs
>>> >'module foo;' distinction. But still this could be anywhere in the
>>> source
>>> >stream. I was able to implement this functionality to a working system.
>>> >
>>> >* Daveed proposed an early signifier of 'hey, this is gonna be a
>>> module', should
>>> >the actual module declaration not be first. Hence 'module;' was born.
>>> (My
>>> >understanding was that this was driven by implementors, as they had
>>> difficulty
>>> >entering a module-like mode not at start of compilation, and indeed it
>>> was a
>>> >little tricky to do that. I do not know if this was also a user request.)
>>> >
>>> >* post p1103, the requirement that everything between 'module;' and the
>>> module
>>> >decl come from #include came to be.
>>> >
>>> >Hope that helps.
>>> >
>>> >I know I've mentioned it more than once, but I find it unsettling, given
>>> there
>>> >was great opposition to there being a (two way?) mapping between file
>>> names and
>>> >module names, that there is a move in the direction of making file names
>>> >'significant'. ISTM that the desire for bob.$REGULARSUFFIX and
>>> >alice.$MODULESUFFIX is taking us all the way back to the first objection
>>> above
>>> >about having two languages.
>>> >
>>> >nathan
>>> >
>>> >
>>> >
>>> >Am 13. April 2022 22:58:13 MESZ schrieb Nicolai Josuttis via Ext
>>> ><ext_at_[hidden]<mailto:ext_at_[hidden]>>:
>>> >
>>> > What I teach about modules is compelling. Programmers like and want
>>> to use it.
>>> > However, they ask how they should organize module files in practice.
>>> >
>>> > So far I cannot recommend a specific suffix (and I might never be
>>> able to do
>>> > that).
>>> > However there is one important question that IMO the standard should
>>> answer:
>>> > *Do we **/need /**different suffixes?*
>>> >
>>> > I understand that a suffix discussion is only of practical value.
>>> > But IMO the standard has to give an answer here (which has nothing
>>> to do
>>> > with which suffixes are used).
>>> >
>>> > Let me elaborate that in detail:
>>> >
>>> > Not having a standard suffix has interesting consequences.
>>> > So far we have header files and translation units.
>>> > But once we know what a C++ translation unit is, we can just compile
>>> them
>>> > all with the same compiler options or commands. Because in practice
>>> we have
>>> > different suffixes for header and source files, we can set-up
>>> generic rules
>>> > to compile our code.
>>> >
>>> > This works for any suffix, provided you know the way to tell the
>>> compiler
>>> > that we have a C++ file here:
>>> > (use /Tp with VC++ and -xc++ with gcc and you are done).
>>> >
>>> > Is this still true with modules?
>>> > That is: Can we expect that identifying a file as C++ file is enough
>>> to be
>>> > able to (pre) compile it as C++ file?
>>> >
>>> > Current compilers give different answers (AFAIK):
>>> >
>>> > - *gcc *says the same suffix is possible. There is not special
>>> option for
>>> > modules.
>>> > I can still have my own suffixes and use -xc++ though.
>>> >
>>> > - *VC++* currently requires different suffixes or different
>>> command-line
>>> > arguments.
>>> > Identifying a file as C++ file is not enough.
>>> > For example
>>> > - This is not enough: /Tp mymod.cppm
>>> > - You need: /interface /Tp mymod.cppm
>>> >
>>> > I wonder whether the behavior of VC++ is standard conforming.
>>> >
>>> > I see no place in the C++ standard saying that there has to be
>>> different
>>> > treatment of C++ source files to make them work.
>>> > Or do we require this somewhere?
>>> > We do not require different treatment just because we have templates,
>>> > namespaces, or exceptions used inside.
>>> > Therefore, I would expect that also using modules does not require
>>> special
>>> > handling.
>>> > (This is independent from the question whether different suffixes
>>> help to
>>> > deal with these files).
>>> >
>>> > If I am right, VC++ is not standard conforming.
>>> >
>>> >
>>> > In any case it would help a lot to clarify:
>>> > Can all C++ source files expect that treating them the same way
>>> works fine?
>>> >
>>> > If not, we obviously need different suffixes. But then we should
>>> clearly say
>>> > so (without necessarily saying which suffix it is).
>>> >
>>> >
>>> > I hope this questions brings us a bit forward to be able teach the
>>> first
>>> > *portable *"hello, modules" example.
>>> >
>>> > Thanks
>>> >
>>> > Nico
>>> >
>>> > --
>>> >
>>> >________________________________
>>> >
>>> > Nicolai M. Josuttis
>>> >
>>> https://nam06.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.josuttis.de%2F&data=05%7C01%7Cgdr%40microsoft.com%7Cbd5d9b59ad484906820b08da1f0cac6f%7C72f988bf86f141af91ab2d7cd011db47%7C1%7C0%7C637856436548406876%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=rGQUFYPVGC6vH5MaGf4q6GG%2BB8fTzeWGtqy%2BSjZ9w30%3D&reserved=0
>>> <
>>> https://nam06.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.josuttis.de%2F&data=05%7C01%7Cgdr%40microsoft.com%7C1610f887a9444406d22e08da1f12de0a%7C72f988bf86f141af91ab2d7cd011db47%7C1%7C0%7C637856463158988825%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=p58c74Uq%2FArsijB%2FZMZFWYQRjVAiDRLXA%2Bc0ARBueXU%3D&reserved=0
>>> >
>>> > +49 (0)531 / 129 88 86
>>> > +49 (0)700 / JOSUTTIS
>>> >
>>> > Books:
>>> > C++:
>>> https://nam06.safelinks.protection.outlook.com/?url=http%3A%2F%2Fcppstd20.com%2F&data=05%7C01%7Cgdr%40microsoft.com%7Cbd5d9b59ad484906820b08da1f0cac6f%7C72f988bf86f141af91ab2d7cd011db47%7C1%7C0%7C637856436548406876%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=3RK5Al6NSQ9aaLx4mj7IAYuvW2IBRAD292Q5A3%2BlZAk%3D&reserved=0,https://nam06.safelinks.protection.outlook.com/?url=http%3A%2F%2Fcppstd17.com%2F&data=05%7C01%7Cgdr%40microsoft.com%7Cbd5d9b59ad484906820b08da1f0cac6f%7C72f988bf86f141af91ab2d7cd011db47%7C1%7C0%7C637856436548406876%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=6HM1W8MPFGlu1AeYoBJHI9IeRXS7VmxTw5w8YTn8FD4%3D&reserved=0,https://nam06.safelinks.protection.outlook.com/?url=http%3A%2F%2Fcppmove.com%2F&data=05%7C01%7Cgdr%40microsoft.com%7Cbd5d9b59ad484906820b08da1f0cac6f%7C72f988bf86f141af91ab2d7cd011db47%7C1%7C0%7C637856436548406876%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=N%2BKcVW0jDyb9rEFMBB1r69HTdjAP%2BJa4STQPn3vs7Z8%3D&reserved=0
>>> ,
>>> >
>>> https://nam06.safelinks.protection.outlook.com/?url=http%3A%2F%2Fcppstdlib.com%2F&data=05%7C01%7Cgdr%40microsoft.com%7Cbd5d9b59ad484906820b08da1f0cac6f%7C72f988bf86f141af91ab2d7cd011db47%7C1%7C0%7C637856436548406876%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=oHQRsZCq6VomTGLKM9tyotrYPxwh3ZocNgZaBeqgOo4%3D&reserved=0,https://nam06.safelinks.protection.outlook.com/?url=http%3A%2F%2Ftmplbook.com%2F&data=05%7C01%7Cgdr%40microsoft.com%7Cbd5d9b59ad484906820b08da1f0cac6f%7C72f988bf86f141af91ab2d7cd011db47%7C1%7C0%7C637856436548406876%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=gVVlDFg7ZDl5T%2Bgcbyf5KrwiqLBOEFfLbSR19DGDMgQ%3D&reserved=0
>>> <
>>> https://nam06.safelinks.protection.outlook.com/?url=http%3A%2F%2Fcppstdlib.com%2F&data=05%7C01%7Cgdr%40microsoft.com%7C1610f887a9444406d22e08da1f12de0a%7C72f988bf86f141af91ab2d7cd011db47%7C1%7C0%7C637856463158988825%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=yOr6zw%2Fn2ieJeu%2FLClrrZO6kgYphCKzAJuLLIvnnX7A%3D&reserved=0
>>> >
>>> >
>>> >--
>>> >Nico Josuttis
>>> >(sent from my mobile phone)
>>> >
>>> >________________________________
>>> >
>>> >SG15 mailing list
>>> >SG15_at_[hidden]<mailto:SG15_at_[hidden]>
>>> >
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>>> <
>>> https://nam06.safelinks.protection.outlook.com/?url=https%3A%2F%2Flists.isocpp.org%2Fmailman%2Flistinfo.cgi%2Fsg15&data=05%7C01%7Cgdr%40microsoft.com%7C1610f887a9444406d22e08da1f12de0a%7C72f988bf86f141af91ab2d7cd011db47%7C1%7C0%7C637856463158988825%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=S6qXqKiRwadGpynz34rxacJtL8HGBj2CJu6gYxoEl4E%3D&reserved=0
>>> >
>>> >
>>> >
>>> >
>>> >--
>>> >Nathan Sidwell
>>> >
>>> >________________________________
>>> >
>>> >Ext mailing list
>>> >Ext_at_[hidden]<mailto:Ext_at_[hidden]>
>>> >Subscription:
>>> https://nam06.safelinks.protection.outlook.com/?url=https%3A%2F%2Flists.isocpp.org%2Fmailman%2Flistinfo.cgi%2Fext&data=05%7C01%7Cgdr%40microsoft.com%7Cbd5d9b59ad484906820b08da1f0cac6f%7C72f988bf86f141af91ab2d7cd011db47%7C1%7C0%7C637856436548406876%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=FKzU3Gsik%2F2SAyJOOmZfJ%2FWTRZ8jjpc4cXaOotkWrB0%3D&reserved=0
>>> <
>>> https://nam06.safelinks.protection.outlook.com/?url=https%3A%2F%2Flists.isocpp.org%2Fmailman%2Flistinfo.cgi%2Fext&data=05%7C01%7Cgdr%40microsoft.com%7C1610f887a9444406d22e08da1f12de0a%7C72f988bf86f141af91ab2d7cd011db47%7C1%7C0%7C637856463158988825%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=Ki7yx7xed6LLVCfthhpH405JRq5l9wW3kF8EQ07ghEY%3D&reserved=0
>>> >
>>> >Link to this post:
>>> https://nam06.safelinks.protection.outlook.com/?url=http%3A%2F%2Flists.isocpp.org%2Fext%2F2022%2F04%2F19021.php&data=05%7C01%7Cgdr%40microsoft.com%7Cbd5d9b59ad484906820b08da1f0cac6f%7C72f988bf86f141af91ab2d7cd011db47%7C1%7C0%7C637856436548406876%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=DjZPo5RuyycaIgn8Yp3q%2BX2kmXv4Oj9lTHkPIsyYk4Q%3D&reserved=0
>>> <
>>> https://nam06.safelinks.protection.outlook.com/?url=http%3A%2F%2Flists.isocpp.org%2Fext%2F2022%2F04%2F19021.php&data=05%7C01%7Cgdr%40microsoft.com%7C1610f887a9444406d22e08da1f12de0a%7C72f988bf86f141af91ab2d7cd011db47%7C1%7C0%7C637856463158988825%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=EJPBQ8G5MLaW0RBVNLud2RWq5gtXAYsk5tJ%2B%2Fct5YIk%3D&reserved=0
>>> >
>>> >
>>> >________________________________
>>> >
>>> >Ext mailing list
>>> >Ext_at_[hidden]<mailto:Ext_at_[hidden]>
>>> >Subscription: https://lists.isocpp.org/mailman/listinfo.cgi/ext<
>>> https://nam06.safelinks.protection.outlook.com/?url=https%3A%2F%2Flists.isocpp.org%2Fmailman%2Flistinfo.cgi%2Fext&data=05%7C01%7Cgdr%40microsoft.com%7C1610f887a9444406d22e08da1f12de0a%7C72f988bf86f141af91ab2d7cd011db47%7C1%7C0%7C637856463158988825%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=Ki7yx7xed6LLVCfthhpH405JRq5l9wW3kF8EQ07ghEY%3D&reserved=0
>>> >
>>> >Link to this post: http://lists.isocpp.org/ext/2022/04/19023.php<
>>> https://nam06.safelinks.protection.outlook.com/?url=http%3A%2F%2Flists.isocpp.org%2Fext%2F2022%2F04%2F19023.php&data=05%7C01%7Cgdr%40microsoft.com%7C1610f887a9444406d22e08da1f12de0a%7C72f988bf86f141af91ab2d7cd011db47%7C1%7C0%7C637856463158988825%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=Qu%2B5DWTdYzn3j6KAhjyM46MwRmpzO3J3Zdd9ljJm5SQ%3D&reserved=0
>>> >
>>> >--
>>> >Nico Josuttis
>>> >(sent from my mobile phone)
>>>
>>> --
>>> Nico Josuttis
>>> (sent from my mobile phone)
>>> _______________________________________________
>>> SG15 mailing list
>>> SG15_at_[hidden]
>>> https://lists.isocpp.org/mailman/listinfo.cgi/sg15
>>>
>> --
>> ---
>> Nicolai M. Josuttiswww.josuttis.de
>> +49 (0)531 / 129 88 86
>> +49 (0)700 / JOSUTTIS
>>
>> Books:
>> C++: http://cppstd20.com, http://cppstd17.com, http://cppmove.com,
>> http://cppstdlib.com, http://tmplbook.com
>>
>>
-- Nico Josuttis (sent from my mobile phone)
Received on 2022-04-16 18:13:13