A const idiom + a different 'delete'

[Andrej Mitrovic]

I think a more appropriate word for that would be "hide", or maybe "freeze".

Here's another alternative, if you can call it that :p :

import std.stdio;

auto freeze(alias dg)()
{
    return cast(const) dg();
}

void main() {
    auto aa = freeze!(
    {
        int[int] aa_;
        foreach (i; 0 .. 10)
            aa_[i] = i * i;

        return aa_;
    });

    writeln(aa, " ", typeid(aa));
}

But that returns const(const(int)[int]).

I'm not sure if there's a way to hide a symbol, appart from introducing
another scope with { }. That wouldn't work in this case, since you want a
const type back. Perhaps using the "variant" type from Phobos could do the
trick.. I haven't played with that yet.

On Wed, Aug 11, 2010 at 6:01 PM, bearophile <bearophileHUGS at lycos.com>wrote:

> > Here delete doesn't clean the aa_, it just removes the aa_ name from the
> local namespace.
>
> It's similar to the #undef directive of C.
>
> Bye,
> bearophile
>
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