Walter Bright wrote:
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
If the annotation (attribute) proposal is adopted (see DIP 6) then
property can be considered a compile-time annotation (attribute) and no
new global keyword is required.
@property @pure @const @nothrow bool empty() { ... }
or
attribute(property,pure,const,nothrow) bool empty() { ... }
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?
Ugly :)
