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digitalmars.D - Why do we have uncommented and undocumented symbols in std.traits?

reply Andrei Alexandrescu <SeeWebsiteForEmail erdani.org> writes:
BooleanTypeOf
IntegralTypeOf
FloatingPointTypeOf
NumericTypeOf
UnsignedTypeOf
SignedTypeOf
CharTypeOf
StaticArrayTypeOf
DynamicArrayTypeOf
ArrayTypeOf
AssocArrayTypeOf
BuiltinTypeOf

Looking at their subtly repetitive definitions, they are specious to 
start with, but they have absolutely no comments so who knows what 
they're useful for.

People ask "what would do phobos better?" and it's ironic because 
literally whatever file I open there are dozens of immediate and urgent 
improvements to be done that scream at you.
May 07
next sibling parent reply Petar Kirov [ZombineDev] <petar.p.kirov gmail.com> writes:
On Friday, 7 May 2021 at 16:31:35 UTC, Andrei Alexandrescu wrote:
 BooleanTypeOf
 IntegralTypeOf
 FloatingPointTypeOf
 NumericTypeOf
 UnsignedTypeOf
 SignedTypeOf
 CharTypeOf
 StaticArrayTypeOf
 DynamicArrayTypeOf
 ArrayTypeOf
 AssocArrayTypeOf
 BuiltinTypeOf

 Looking at their subtly repetitive definitions, they are 
 specious to start with, but they have absolutely no comments so 
 who knows what they're useful for.

 People ask "what would do phobos better?" and it's ironic 
 because literally whatever file I open there are dozens of 
 immediate and urgent improvements to be done that scream at you.
As far as I can tell from the [PR][0] that added them, they were needed so that `std.format` can treat `struct S(T) { T x; alias x this; }` as `T` if `T` is a built-in type, by having `AbcTypeOf!(S(T))` yield `T`, if `T` is `Abc` (e.g. Boolean, FloatingPoint, etc.) in template constraints. In other words, it looks like they were meant only for Phobos-internal use. These days, we use `package (std)` for such symbols. Perhaps that `package` protection attributes were not implemented (or not working reliably) in ~2012? There is no discussion in that pull request, so perhaps you had discussed the matter with Kenji either on the newsgroup, Bugzilla, in other pull request, or privately? [0]: https://github.com/dlang/phobos/pull/488
May 07
parent Andrei Alexandrescu <SeeWebsiteForEmail erdani.org> writes:
On 5/7/21 4:50 PM, Petar Kirov [ZombineDev] wrote:
 On Friday, 7 May 2021 at 16:31:35 UTC, Andrei Alexandrescu wrote:
 BooleanTypeOf
 IntegralTypeOf
 FloatingPointTypeOf
 NumericTypeOf
 UnsignedTypeOf
 SignedTypeOf
 CharTypeOf
 StaticArrayTypeOf
 DynamicArrayTypeOf
 ArrayTypeOf
 AssocArrayTypeOf
 BuiltinTypeOf

 Looking at their subtly repetitive definitions, they are specious to 
 start with, but they have absolutely no comments so who knows what 
 they're useful for.

 People ask "what would do phobos better?" and it's ironic because 
 literally whatever file I open there are dozens of immediate and 
 urgent improvements to be done that scream at you.
As far as I can tell from the [PR][0] that added them, they were needed so that `std.format` can treat `struct S(T) { T x; alias x this; }` as `T` if `T` is a built-in type, by having `AbcTypeOf!(S(T))` yield `T`, if `T` is `Abc` (e.g. Boolean, FloatingPoint, etc.) in template constraints.
Thanks. Ah, our old friend "alias this" to be weirdly supported everywhere. That code must be removed at once with maximum prejudice.
 In other words, it looks like they were meant only for Phobos-internal 
 use. These days, we use `package (std)` for such symbols. Perhaps that 
 `package` protection attributes were not implemented (or not working 
 reliably) in ~2012?
 
 There is no discussion in that pull request, so perhaps you had 
 discussed the matter with Kenji either on the newsgroup, Bugzilla, in 
 other pull request, or privately?
 
 [0]: https://github.com/dlang/phobos/pull/488
I made a terrible mistake accepting that PR.
May 07
prev sibling parent Basile B. <b2.temp gmx.com> writes:
On Friday, 7 May 2021 at 16:31:35 UTC, Andrei Alexandrescu wrote:
 BooleanTypeOf
 IntegralTypeOf
 FloatingPointTypeOf
 NumericTypeOf
 UnsignedTypeOf
 SignedTypeOf
 CharTypeOf
 StaticArrayTypeOf
 DynamicArrayTypeOf
 ArrayTypeOf
 AssocArrayTypeOf
 BuiltinTypeOf

 Looking at their subtly repetitive definitions, they are 
 specious to start with, but they have absolutely no comments so 
 who knows what they're useful for.

 People ask "what would do phobos better?" and it's ironic 
 because literally whatever file I open there are dozens of 
 immediate and urgent improvements to be done that scream at you.
 [The entire SomethingTypeOf idiom has smell. It is pedestrian, 
 repetitive, and arcane - everything NOT characteristic to good 
 D code. I am sorry I have allowed these symbols in the first 
 place, doubly so for not figuring out they added undocumented 
 public symbols, triply so that so much time has passed 
 since.](https://github.com/dlang/phobos/pull/5747#issuecomment-333421636)
Nobody agreed on the path to follow.
May 07