On 09/25/2012 11:01 PM, Andrei Alexandrescu wrote:
On 9/25/12 4:14 PM, Jonathan M Davis wrote:
On Wednesday, September 26, 2012 04:29:13 kenji hara wrote:
But, the two are often confused, by the word "tuple". It has
introduced badly confusion in many discussions.
To make matters worse, it had often invoked incorrect suggestion that
merging the two into one.
My suggestion is very simple.
1. Change all words "built-in tuple" in the documentation to "built-in
sequence". Then, in the D language world, we can have clarify name for
the built-in one.
2. Introduce new templates, Seq, TypeSeq, and ExpSeq.
template Seq(T...) { alias T Seq; } // identical with
std.typetuple.TypeTuple
template TypeSeq(T...) if (allSatisfy!(isType, T)) { alias T TypeSeq; }
template ExpSeq(T...) if (allSatisfy!(isExpression, T)) { alias T
ExpSeq; }
If you really want to a sequence with heterogeneous elements, use
Seq template. Otherwise use TypeSeq or ExpSeq based on your purpose.
In principle, renaming TypeTuple makes sense given it's bad name
(though I
really don't seem much point in separating expression tuples and type
tuples),
but it would break a _lot_ of code. And both Walter and Andrei are
increasingly against making any breaking changes.
- Jonathan M Davis
TypeTuple does a lot of harm. I'd be glad to rename it GenericTuple and
leave TypeTuple as a slowly rotting alias.
Andrei
I'd never use GenericTuple, because already after four usages it would
have been cheaper to just define Seq inline.
GenericTupleGenericTupleGenericTupleGenericTuple
template Seq(T...){ alias T Seq; }SeqSeqSeqSeq
What is the rationale for calling this construct a tuple anyway?
Programming language tuples usually impose more structure on the
data than just ordering.
