Ben Noordhuis f11b948019 allow implicit cast from S to ?&const S
Allow implicit casts from container types to nullable const pointers to
said container type.  That is:

    fn f() void {
        const s = S {};
        g(s);   // Works.
        g(&s);  // So does this.
    }

    fn g(_: ?&const S) void {  // Nullable const pointer.
    }

Fixes #731.
2018-02-23 15:55:57 +01:00
..
2018-02-09 18:27:50 -05:00