int => struct cast

[Max Samukha]

On Thu, 02 Oct 2008 10:04:18 -0400, bearophile
<bearophileHUGS at lycos.com> wrote:

>Why can't I cast  an n int to a struct with only a x int field?
>Time ago someone has said that all internal errors are problems, is this known and bad?
>
>struct S { int x; }
>void main() {
>    int n = 1;
>    int[S] a;
>    a[ cast(S)n ]++;
>}
>
>OUTPUT DMD 1.035:
>temp.d(5): Error: e2ir: cannot cast from int to S
>Internal error: e2ir.c 3904
>
>Bye,
>bearophile

There is a not well documented feature that turns cast(S)n into S(n),
if opCall is defined

struct S {
  int x;
   static S opCall(int x) { S r; r.x = x; return r; } 
}

void main() {
    int n = 1;
    int[S] a;
    a[ cast(S)n ]++;
}