DIP19: Remove comma operator from D and provision better syntactic support for tuples

[Michael]

On Sunday, 23 September 2012 at 20:39:38 UTC, Andrei Alexandrescu 
wrote:
> I discussed this with Walter, and we concluded that we could 
> deprecate the comma operator if it helps tuples. So I started 
> with this:
>
> http://www.prowiki.org/wiki4d/wiki.cgi?LanguageDevel/DIPs/DIP19
>
> Unfortunately, I started much cockier than I ended. The 
> analysis in there fails to construct a case even half strong 
> that deprecating the comma operator could significantly help 
> tuples. Well it essentially concludes that tuples are mostly 
> fine as they are, and attempts to embellish them syntactically 
> are marred with unexpected problems. Nevertheless, I sure have 
> missed aspects all over, so contributions are appreciated.
>
>
> Thanks,
>
> Andrei

With removed comma operator from D next code will work?

module maybe;

import std.stdio;
import std.algorithm;

R  With(I, R)(I o, R function (I) fun)
{
	return o is null ? null : fun(o);
}

R Return(I, R)(I o, R function (I) fun, R failureResult)
{
	return o is null ? failureResult : fun(o);
}

I If(I)(I o, bool function (I) fun)
{
	return o is null ? null : fun(o) ? o : null;
}

I Unless(I)(I o, bool function (I) fun)
{
	return o is null ? null : fun(o) ? null : o;
}

I Do(I)(I o, void function (I) fun)
{
	return o is null ? null : fun(o), o;
}

void doit(string value)
{
	writeln("Loading... \n");
}


void main()
{
	string name = "D";

	name = name.With((string x) => "Hello, " ~ x ~ "!").
				If((string x) => canFind(x, "D")).
				Do((string x) => x.doit).
				Return((string x) => x ~ " I love You!", "Oh, my!");
	
	writeln(name);
}


especially template function

I Do(I)(I o, void function (I) fun)
{
	return o is null ? null : fun(o), o;
}