Wrap + add methods?

[Steven Schveighoffer]

On 6/28/21 11:53 AM, Paul Backus wrote:
> On Monday, 28 June 2021 at 15:17:34 UTC, Steven Schveighoffer wrote:
>> I have a situation where I want to wrap a certain type to add a few 
>> methods to that type.
>>
>> UFCS is not an option, because the library that will use this type 
>> will not import the UFCS methods.
>>
>> `std.typecons.Proxy` doesn't seem to wrap static methods, and besides, 
>> I want to return wrappers if the function being wrapped returns the 
>> same type (this is critical for stuff like `auto result = a + b`, I 
>> want the result to be the same wrapped type).
>>
>> Are there any libraries that might do this (including Phobos)?
> 
> https://code.dlang.org/packages/addle
> 
> Doesn't do everything you're looking for, but you might find some useful 
> tricks in the source.

Very neat! I think I can't use it, because I need to add static methods.

My particular use case is a translated database type. In this case, it's 
a fixed point currency, which is stored as an integer in the database, 
but translated to a D fixedpoint type.

To make it work with my DB library, I need to have a method `dbValue` 
which converts the D type into an appropriate D type that the database 
can utilize (long in this case), and a static method `fromDBValue` which 
goes the opposite direction.

For now, I've just hand implemented the needed functions. This includes 
forwarding constructors, operator overloads, opAssign, etc.

-Steve