Alias template parameters and runtime functions

[bearophile]

Peter Alexander:

> class Foo
> {
>   int[] data;
> 
>   int foo(int i) { return data[i]; }
> 
>   auto allFoo()
>   {
>     auto fun = (int i) { return foo(i); };
>     // alternatively: auto fun = &this.foo; (same result)
>     return map!(fun)(iota(data.length));
>   }
> }
> 
> This compiles, but gives you an access violation when you try to use it.

But that code works with dmd 2.049:

import std.algorithm: map, equal;
import std.range: iota;

class Foo {
    int[] data;

    this(int[] a) { this.data = a.dup; }

    int foo(int i) { return data[i] * 2; }

    auto allFoo1() {
        auto fun = (int i) { return foo(i); };
        return map!(fun)(iota(data.length));
    }

    auto allFoo2() {
        return map!((int i){ return foo(i); })(iota(data.length));
    }
}

void main() {
    auto f = new Foo([1, 2, 3]);
    assert(equal(f.allFoo1(), [2, 4, 6]));
    assert(equal(f.allFoo2(), [2, 4, 6]));
}


Bye,
bearophile