Passing $ as a function argument

[James Japherson]

Would be nice to be able to pass $ as a function argument to be 
used in automatic path length traversing.


void foo(int loc)
{
    return bar[loc];
}

then foo($) would essentilly become

foo(&)

   becomes ==>

    return bar[$];


instead of having do to thinks like foo(bar.length).

The usefulness comes from the case when bar is local:

void foo(int loc)
{
    auto bar = double[RandomPInt+1];

    return bar[loc];
}


then foo($) always returns a value and the outside world does not 
need to know about foo. Since $ is a compile thing expression and 
not used anywhere else this can always be done(it is a symbolic 
substitution and has a direct translation in to standard D code 
except $ cannot be used as arguments like this the current D 
language grammar).