I have:

Grapheme[] gr;
dchar[1] buf;
encode(buf, cast(dchar)myData);
gr =~ decodeGrapheme(buf[]);

Which gives:

Error: template std.uni.decodeGrapheme cannot deduce function from argument types !()(dchar[]), candidates are:
C:\D\dmd2\windows\bin\..\..\src\phobos\std\uni.d(7164,10):        decodeGrapheme(Input)(ref Input inp)

I some how need an InputRange for buf and though that buf[] should work. But it doesn't seem to be an L-value... which I don't understand. I thought buf[] returns a temporary dynamic array initialized with the buf content.

-- 
Robert M. Münch
http://www.saphirion.com
smarter | better | faster

On Saturday, 4 January 2020 at 19:56:54 UTC, Robert M. Münch wrote:
> But it doesn't seem to be an L-value... which I don't understand. I thought buf[] returns a temporary dynamic array initialized with the buf content.

The problem here is indeed ref, the function there tries to update the slice so it point to the next element and that requires a named variable.

Generally speaking, if your thing is not tied directly to a named variable it can update, it cannot be ref.

So your buf[] there refers to a named variable, which is good enough... but the [] cannot possibly update because buf is statically sized.

Just assigning to a temporary in the middle can fix this for you:

dchar[] remainingItems = buf[];
decode(remainingItems);
// note that length of remainingItems will now be smaller than it started