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digitalmars.D - Concatenating Tuples

reply dsimcha <dsimcha yahoo.com> writes:
Is there a way to concatenate tuples at compile time in D2?  The obvious ~
operator doesn't work on tuples.  Also, while I'm at it, maybe there's a
better way to achieve my end goal here.  Is there a way to get a tuple
representation of a class object that includes the stuff from the base classes?
Oct 14 2008
parent reply BCS <ao pathlink.com> writes:
Reply to dsimcha,


 Is there a way to concatenate tuples at compile time in D2?  The
 obvious ~ operator doesn't work on tuples.  Also, while I'm at it,
 maybe there's a better way to achieve my end goal here.  Is there a
 way to get a tuple representation of a class object that includes the
 stuff from the base classes?
 


just put them side by side.

template Tpl(T...) { alias T Tpl; }

alias Tpl!(a,b,c) A;
alias Tpl!(d,e,f) B;
alias Tpl!(A,B) C;
Oct 14 2008
parent reply dsimcha <dsimcha yahoo.com> writes:
== Quote from BCS (ao pathlink.com)'s article

 Reply to dsimcha,

 Is there a way to concatenate tuples at compile time in D2?  The
 obvious ~ operator doesn't work on tuples.  Also, while I'm at it,
 maybe there's a better way to achieve my end goal here.  Is there a
 way to get a tuple representation of a class object that includes the
 stuff from the base classes?


 just put them side by side.
 template Tpl(T...) { alias T Tpl; }
 alias Tpl!(a,b,c) A;
 alias Tpl!(d,e,f) B;
 alias Tpl!(A,B) C;


Sorry for the poorly worded question.  What you suggested would work for type
tuples.  I'm looking for a way to do this for value tuples, i.e. the kind you
would get from Object.tupleof.
Oct 14 2008
parent reply BCS <ao pathlink.com> writes:
Reply to dsimcha,


 == Quote from BCS (ao pathlink.com)'s article
 

 Reply to dsimcha,
 

 Is there a way to concatenate tuples at compile time in D2?  The
 obvious ~ operator doesn't work on tuples.  Also, while I'm at it,
 maybe there's a better way to achieve my end goal here.  Is there a
 way to get a tuple representation of a class object that includes
 the stuff from the base classes?
 


 just put them side by side.
 template Tpl(T...) { alias T Tpl; }
 alias Tpl!(a,b,c) A;
 alias Tpl!(d,e,f) B;
 alias Tpl!(A,B) C;


 Sorry for the poorly worded question.  What you suggested would work
 for type tuples.  I'm looking for a way to do this for value tuples,
 i.e. the kind you would get from Object.tupleof.
 


That should work there as well, if it dosn't work, it's a bug. (I think).
Oct 14 2008
parent reply dsimcha <dsimcha yahoo.com> writes:
== Quote from BCS (ao pathlink.com)'s article

 Reply to dsimcha,

 == Quote from BCS (ao pathlink.com)'s article


 Reply to dsimcha,


 Is there a way to concatenate tuples at compile time in D2?  The
 obvious ~ operator doesn't work on tuples.  Also, while I'm at it,
 maybe there's a better way to achieve my end goal here.  Is there a
 way to get a tuple representation of a class object that includes
 the stuff from the base classes?


 just put them side by side.
 template Tpl(T...) { alias T Tpl; }
 alias Tpl!(a,b,c) A;
 alias Tpl!(d,e,f) B;
 alias Tpl!(A,B) C;


 Sorry for the poorly worded question.  What you suggested would work
 for type tuples.  I'm looking for a way to do this for value tuples,
 i.e. the kind you would get from Object.tupleof.


 That should work there as well, if it dosn't work, it's a bug. (I think).


Sorry, you're right.  My bad.  I thought I already had tried this and it didn't
work but I guess not.  Seems to work now.
Oct 14 2008
parent reply dsimcha <dsimcha yahoo.com> writes:
== Quote from dsimcha (dsimcha yahoo.com)'s article

 == Quote from BCS (ao pathlink.com)'s article

 Reply to dsimcha,

 == Quote from BCS (ao pathlink.com)'s article


 Reply to dsimcha,


 Is there a way to concatenate tuples at compile time in D2?  The
 obvious ~ operator doesn't work on tuples.  Also, while I'm at it,
 maybe there's a better way to achieve my end goal here.  Is there a
 way to get a tuple representation of a class object that includes
 the stuff from the base classes?


 just put them side by side.
 template Tpl(T...) { alias T Tpl; }
 alias Tpl!(a,b,c) A;
 alias Tpl!(d,e,f) B;
 alias Tpl!(A,B) C;


 Sorry for the poorly worded question.  What you suggested would work
 for type tuples.  I'm looking for a way to do this for value tuples,
 i.e. the kind you would get from Object.tupleof.


 That should work there as well, if it dosn't work, it's a bug. (I think).


 Sorry, you're right.  My bad.  I thought I already had tried this and it didn't
 work but I guess not.  Seems to work now.


Ok, now I know why this has been so weird.  Looks like we do have a legit bug
here.  Your suggestion works in the toy case, but not in my actual use case. 
I'll
file this in Bugzilla if someone else hasn't found it already.

//The following works.
import std.stdio, std.typetuple;

void main() {
    auto foo = TypeTuple!("1 ", "2 ");
    auto bar = TypeTuple!("3");
    writeln(TypeTuple!(foo, bar));
}

//The following doesn't work.

import std.stdio, std.typetuple;

void main() {
    auto foo = new Foo;
    writeln(TypeTuple!(foo.tupleof));
}

Error messages:

D:\code\test\test3.d|13|Error: tuple is not a valid template value argument|
E:\dmd\bin\..\src\phobos\std\typetuple.d|13|template instance
std.typetuple.TypeTuple!(tuple((Foo).a)) error instantiating|
Oct 14 2008
parent "Jarrett Billingsley" <jarrett.billingsley gmail.com> writes:
On Wed, Oct 15, 2008 at 12:05 AM, dsimcha <dsimcha yahoo.com> wrote:


 //The following doesn't work.

 import std.stdio, std.typetuple;

 void main() {
    auto foo = new Foo;
    writeln(TypeTuple!(foo.tupleof));
 }

 Error messages:

 D:\code\test\test3.d|13|Error: tuple is not a valid template value argument|
 E:\dmd\bin\..\src\phobos\std\typetuple.d|13|template instance
 std.typetuple.TypeTuple!(tuple((Foo).a)) error instantiating|


http://d.puremagic.com/issues/show_bug.cgi?id=1670
Oct 15 2008