Hi!

Consider this simplified program:
```
import std.stdio;

struct X {
    void method(int x) {
        writeln("method called");
    }
}


void main() {
    X x;

    foreach (member; __traits(allMembers, X)) {
        alias method = __traits(getMember, x, member);
        method(1);
    }
}
```

Output:
test.d(15): Error: need this for method of type void(int x)



This one as well:
```
import std.stdio;

struct X {
    void method(int x) {
        writeln("method(int) called");
    }
}


struct Y {
    void method(ref X x) {
        foreach (member; __traits(allMembers, X)) {
            alias method = __traits(getMember, x, member);
            method(1);
        }
    }
}


void main() {
    Y y;
    X x;
    y.method(x);
}
```

Output:
```test.d(14): Error: this for method needs to be type X not type Y```


This is a bug, right? If not, why, and how can I get around it and call `method`?

On Wednesday, 23 October 2019 at 11:40:09 UTC, Márcio Martins wrote:
> This is a bug, right? If not, why, and how can I get around it and call `method`?

An alias refers just to a symbol, in this case a member function of struct X.
The fact that you polled it on instance 'x' is not something an alias keeps track of.
You can change `method(1)` into `x.method(1)` and it should work.

On Wednesday, 23 October 2019 at 11:48:29 UTC, Dennis wrote:
> You can change `method(1)` into `x.method(1)` and it should work.

Wait, but that's only because the local alias and member function have the same name 'method'.
I think you just have to keep the method name as a string instead of an alias and use ` __traits(getMember, x, member)(3);` the moment you want to call it.