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Subject: Re: [boost] Call for interest - BOOST_AUTO_FUNCTION
From: David Sankel (camior_at_[hidden])
Date: 2010-10-05 22:50:23

On Tue, Oct 5, 2010 at 3:20 PM, Matt Calabrese <rivorus_at_[hidden]> wrote:

> I've been noticing that a lot of times in 0x code I've found it useful to
> create a very simple "auto function" macro that uses trailing return type
> syntax with decltype with 1-liner functions that automatically repeats the
> same expression in both the return type and the return statement.
> #define AUTO_FUN( name, param_list, expression )
> \
> auto name param_list -> decltype( expression ) { return expression; }

It's very aggravating that C++-0x didn't include include a function
definition syntax like this from the start. A large chunk of the functions I
write are 1-liners so the problem you're describing certainly applies to me.

I've been using the following syntax wherever feasible:

auto f = //some lambda or De Bruijn Bind expression

That solves the repetition problem, but the code looses resemblance to
typical C++ at that point.

Although your solution works well, I think it is incredibly inelegant when
compared to a C++ language fix. Can't we solve this problem cleanly and
quickly? I'd really hate to see heaps of AUTO_FUN code created while we wait
12 years for the improvement in C++ syntax.

So, personally I would not like to see this in boost. I'd like to see a
clean solution in all standards conforming compilers.


David Sankel
Sankel Software
585 617 4748 (Office)

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