Simplifing tuples
chris jefferson
caj@cs.york.ac.uk
Sun Oct 10 18:00:00 GMT 2004
Paolo Carlini wrote:
> chris wrote:
>
>> I'm currently working my way through implementing this, writing a
>> sizeable test suite, etc. I just wondered if anyone had any positive
>> / negative comments on this kind of unfolding?
>
>
> Something I'm wondering about is whether we can provide to the user a
> *simple* way to *set* (at library build time) the maximum number of
> elements in one tuple type, not just 10, as mandated by the standard,
> or an arbitrary number decided by the implementors: AFAICS this is not
> possible neither with boost reference implementation, neither with
> your proposal. Of course, it's something highly not trivial,
> preprocessor magic and/or sophisticated template metaprogramming
> techniques would be needed, but eventually the QoI would be much
> higher, IMHO...
> .
Actually, with my current iml[ementation this owuld be possible, as I
have a c++ program (although this could easily be converted to C) which
generates the tuple header takes a parameter which defines the maximum
size of tuple. I'm curerntly testing with this parameter set to 3 so
it's easier to see whats going on and debug. I suspect it could be done
with preprocessor and templateness, but it wouldn't be very pretty :)
And like all processor magic it would still require some kind of
hard-wired maximum.
I'm still torn on wether I should generate the header with C or with
template metaprogramming. Having discussed it with a few people, the
arguments fall into one of two categories:
1) Why write a C program to output the header when you could do it with
templates?
2) Why write complex templates to generate the tuples when you could
just write a simple C program to output the header?
:)
Chris
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