Should we deprecate comma?

[bearophile]

Dicebot:

> I understand but this is something that can be pretty hard to 
> fit into D semantics/grammar and I am not sold that it is worth 
> the push on its own.

I'd like a good tuple syntax in D.


> What is the difference with this then?
>
> void foo(int a, int b, int c)
> {
>     // ...
> }
>
> auto t = tuple(10, 20, 30);
> foo(t.expand);

The difference is that your experience with tuples will be less 
good. One difference can be seen here. Given an array of tuples 
(here I am using a shorter syntax):

auto arr = [@{1, 2}, @(3, 4)]

You can't do this:

void foo(int a, int b, int c) {...}
auto result = arr.map!foo;

And you need:

auto result = arr.map!(t => foo(t.expand));

Or:

auto result = arr.map!(t => foo(t[]));


While you can do this:

void foo(in @(int a, int b, int c}) {...}
auto result = arr.map!foo;

The point of having a tuple syntax is not to expand the set of 
programs you can write with C language. It's of having a handy 
syntax to perform certain very common operations with more than 
one type.

I also suggest you to take a look at the DIP.

Bye,
bearophile