property syntax strawman

[Walter Bright]

Having optional parentheses does lead to unresolvable ambiguities. How 
much of a problem that really is is debatable, but let's assume it 
should be resolved. To resolve it, a property must be distinguishable 
from a regular function.

One way is to simply add a "property" attribute keyword:

   property bool empty() { ... }
   property void empty(bool b) { ... }

The problem is that:

1. there are a lot of keywords already
2. keywords are global things

The alternative is to have a unique syntax for properties. Ideally, the 
syntax should be intuitive and mimic its use. After much fiddling, and 
based on n.g. suggestions, Andrei and I penciled in:

   bool empty { ... }
   void empty=(bool b) { ... }

The only problem is when a declaration but not definition is desired:

   bool empty;

but oops! That defines a field. So we came up with essentially a hack:

   bool empty{}

i.e. the {} means the getter is declared, but defined elsewhere.

What do you think?