Enforcing static closure

[Piotr Szturmaj]

I want to make a delegate of blocking I/O statement and pass it to a 
function. Then it will be called immediately. This delegate never 
escapes its creation scope, so I don't want heap closure allocation.

Will compiler create dynamic closure (e.g. with allocation) or static 
closure (with pointer to the stack)?

void recv(ubyte[] buf, out size_t len)
{
    // block until data is received
}

int numWaiters;

// will that "scope" enforce static closure?
void wait(scope void delegate() dg)
{
    numWaiters++;
    dg();
    numWaiters--;
}

void test()
{
    ubyte[] buf = new ubyte[1500];
    size_t len;

    wait( { recv(buf, len); } );
}