Precedences of unary minus and dot operators

[inout]

On Friday, 8 November 2013 at 12:49:38 UTC, bearophile wrote:
> This is something that has come out of a thread I have opened 
> in D.learn.
>
> In the thread qznc has answered me:
>
>> Operator precedence of "." is higher than unary minus.
>
>
> That's right:
>
>
> double foo(in double x) {
>     assert (x >= 0);
>     return x;
> }
> void main() {
>     assert(-1.foo == -1);
> }
>
>
> Is this a good design of the operator precedences? Is this 
> worth changing/fixing?
>
> Bye,
> bearophile

struct Foo
{
     int value = 9;
};

struct Bar
{
     // implements unary minus
     int value = 9;
};

int squareRoot(Bar bar) { return sqrt(bar.value); }

int main() {
   Foo foo;
   writeln(-foo.value); // prints -9, by first getting the value 
and then negating it

   Bar bar;
   writeln(-bar.squareRoot); // for consistency, this should also 
call squareRoot first
   // otherwise, the order of operations would depend on whether 
the struct has opUnary implemented