What type does byGrapheme() return?

[H. S. Teoh]

On Tue, Dec 31, 2019 at 04:02:47PM -0500, Steven Schveighoffer via Digitalmars-d-learn wrote:
> On 12/31/19 2:58 PM, H. S. Teoh wrote:
> > On Tue, Dec 31, 2019 at 09:33:14AM -0500, Steven Schveighoffer via Digitalmars-d-learn wrote:
> > > e.g.:
> > > 
> > > writeln(" Text = ", gr1.map!((ref g) => g[]).joiner.to!string);
> > [...]
> > 
> > Unfortunately this doesn't work. Somehow the ref parameter doesn't
> > match whatever it is std.algorithm.map is trying to pass to it.
> 
> Huh, it seemed to work for me. Got the full "Robert" with an R. map
> does support ref-ness. Maybe you didn't put ref in the right place?

Here's my full non-working code:

	import std;
	void main() {
		auto x = "Bla\u0301hbla\u0310h\u0309!";
		auto r = x.byGrapheme;
		writefln("%s", r.map!((ref g) => g[]).joiner.to!string);
	}

The compiler says:

	/usr/src/d/phobos/std/algorithm/iteration.d(604): Error: template D main.__lambda1 cannot deduce function from argument types !()(Grapheme), candidates are:
	test.d(5):        __lambda1
	/usr/src/d/phobos/std/algorithm/iteration.d(499): Error: template instance test.main.MapResult!(__lambda1, Result!string) error instantiating
	test.d(5):        instantiated from here: map!(Result!string)

What did I do wrong?


T

-- 
What do you get if you drop a piano down a mineshaft? A flat minor.