How to pass an InputRange of dchars to a function that wants an Input range of chars?

[monkyyy]

On Wednesday, 19 February 2025 at 20:46:24 UTC, realhet wrote:
> On Wednesday, 19 February 2025 at 19:08:07 UTC, bauss wrote:
>> On Wednesday, 19 February 2025 at 18:13:24 UTC, realhet wrote:
>>>
>>> ...
>>> 
>>
>> std.conv.to can convert for you.
>
> Thx!
>
> I tried .map!(to!dchar) instead of .byChar and it still failed.
>
> But then I deleted the constraints where I detect if the 
> parameter is an input range of a char, and it suddenly worked.
>
> So this
> ```
> if(isInputRange!(R, immutable char))
> ```
> wont let through obvious ranges that are input ranges and 
> contain chars...
>
> Anyone have a clue why?
>
> What constraint should I use then?

import std;
auto fixstring(string s)=>(cast(ubyte[])s).map!(a=>cast(char)a);
void main(){
     "hello 
world".fixstring.map!(a=>std.ascii.toUpper(a)).each!write;
}