Partial function application (Currying)

[atzensepp]

On Saturday, 20 January 2024 at 20:58:49 UTC, Richard (Rikki) 
Andrew Cattermole wrote:
> On 21/01/2024 9:55 AM, atzensepp wrote:
>> import std.stdio; // Overloads are resolved when the partially 
>> applied function is called // with the remaining arguments. 
>> struct S { static char fun(int i, string s) { return s[i]; } 
>> static int fun(int a, int b) { return a * b; } } void main() { 
>> alias fun3 = partial!(S.fun, 3); writeln(fun3("hello")); // 
>> 'l' writeln(fun3(10)); // 30 }
>
> This worked:
>
> ```d
> import std.functional;
> import std.stdio;
>
> // Overloads are resolved when the partially applied function 
> is called
> // with the remaining arguments.
> struct S
> {
>     static char fun(int i, string s)
>     {
>         return s[i];
>     }
>
>     static int fun(int a, int b)
>     {
>         return a * b;
>     }
> }
>
> void main()
> {
>     alias fun3 = partial!(S.fun, 3);
>     writeln(fun3("hello")); // 'l'
>     writeln(fun3(10)); // 30
> }
> ```
Hello Rikki,
thank you, this helps a lot although the polymorphism does not 
work in my environment.
```
partial2.d:23:17: error: function std.functional.partial!(fun, 
3).partial (string _param_0) is not callable using argument types 
(int)
      writeln(fun3(10)); // 30

```
But when I rename the functions for each case currying works well.