On Wednesday, 23 September 2015 at 19:28:03 UTC, Nick Sabalausky
wrote:
On 09/23/2015 03:18 PM, Chad Joan wrote:
This is why I argued for alternative mixin syntax in D some
... years?
... ago.
It'd be really cool to have a writefln overload that did this:
int somevar = 42;
writefln#("This is ${somevar}");
writefln#("Plus two and you get ${somevar+1}");
Which would just be shorthand for
int somevar = 42;
mixin writefln!("This is ${somevar}");
mixin writefln!("Plus two and you get ${somevar+2}");
I feel like a bit of syntax sugar could go a long way ;)
Yea, the trouble with string mixins is that they're ugly enough
people don't like to use them.
I'd argued in the past for a way to tag a CTFE-able
string-returning function as being intended for mixing-in, so
you could omit the "mixin(...)" part. But we only ever got it
for template mixins. Allowing it for string mixins was too
controversial. :(
I dunno, maybe even a string mixin sugar as simple as this
would be a big help:
mixin!func(args to func here)
ie:
mixin!interp("Some string here")
But I'm guessing the ship's ling since sailed for anything like
that.
I hope not :(
I remember when Walter originally designed mixins, he stated
something to the effect that he wanted them to be easily
greppable at all times.
I would argue that they are so centrally important that they
should be a symbol rather than a keyword. Still greppable. But
also much more useful.
Since D already has the mixin keyword, I suspect it would be more
practical to just ask people to grep for 'mixin|<mixin symbol>'
instead of just 'mixin'.
There are similar (but orthogonal) concerns with delegate
(anonymous function) nesting:
// D notation.
foo ( (x,y) {
auto z = doSomething(x+y);
return z*z;
});
vs
// Speculative notation.
foo() : (x,y) {
auto z = doSomething(x+y);
return z*z;
}
Current D notation for nesting functions reminds me of C's
notation for structs...
// C notation.
typedef struct WhatDoIPutHereFoo
{
int x,y;
} Foo;
// D notation. (Yay, consistency!)
struct Foo
{
int x,y;
}
Extra semicolon and syntax noise and such.
I'm still incredibly glad D even has delegates and mixins at this
point ;)
