Re: tuples in C++11

From:

Victor Bazarov <v.bazarov@comcast.invalid>

Newsgroups:

comp.lang.c++

Date:

Tue, 14 Aug 2012 16:39:25 -0400

Message-ID:

<k0ed1u$ti1$1@dont-email.me>

On 8/14/2012 3:15 PM, Single Stage to Orbit wrote:

On Tue, 2012-08-14 at 20:43 +0200, Marcel M??ller wrote:

[ snip ]

No, this is not possible. The compiler cannot know, which function to
call, because at the compile time j does not have a value. In fact

you

want to call /another/ function at each loop iteration.
Furthermore i.get<0> and i.get<1> do not have the same type in

general.

So the compiler cannot know the type of the expression get<j>.

Your code requires run time polymorphism rather than compile time
polymorphism.

Right, I see.

If you want to iterate over the components of your tuple and if all
components have the same type then tuple<> is not the solution. This

a vector (in the mathematical sense). The C++ equivalent of a vector
with a constant length is simply int[3]. I.e.:

They won't all be the same types eventually - it was just an experiment
to see what I can do with tuples using the index into the tuple to
retrieve things.

If they are going to be different types, a function like I suggested
won't work (they need to be of the same type - the return value type of
that function, of course).

V
--
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