Without D1-style operator overloads, the `in` operator for classes doesn't make sense
schveiguy at gmail.com
Mon Jan 6 14:14:35 UTC 2020
On 1/6/20 6:16 AM, Ontonator wrote:
> On Monday, 6 January 2020 at 10:55:15 UTC, Don wrote:
>> In DMD 2.088.0, the D1 operator overloads were deprecated, in favour
>> of the D2 syntax which has been available for years.
> I’m on my phone right now, so I can’t check, but could you emulate a
> virtual operator by creating a virtual method (e.g. `contains`) which is
> called from the operator and which child classes could override? It
> isn’t as ergonomic, but it should work.
In fact this is exactly why this change was allowed (and this exact
problem was discussed):
int* opIn(string key); // virtual
auto opBinaryRight(string op : "in", X)(X key) // wrapper
So when/if the D1 operators get removed, you put this wrapper in, and it
In fact, you can easily make a mixin template that will implement all
the D2 style operators when you have defined the D1 style ones.
More information about the Digitalmars-d