ADL

[Walter Bright via Digitalmars-d]

On 9/3/2016 2:37 AM, Manu via Digitalmars-d wrote:
> On 3 September 2016 at 18:56, Walter Bright via Digitalmars-d
> <digitalmars-d at puremagic.com> wrote:
>> On 9/3/2016 1:37 AM, Walter Bright wrote:
>>>
>>> I thought #4 in particular was rather cool, I plan to use it as an
>>> example.
>>
>>
>> https://github.com/dlang/phobos/pull/4762
 > Complexity ramps up further if there are N arguments to the algorithm.
 > It needs to search each of the arguments modules.

I suggest posting the actual problems you're having, because twice now you've 
gotten solutions to the problems you posted, then said they weren't your actual 
problems.


This template:

// Find module in which T was defined
template ModuleOf(alias T)
{
     import std.traits : moduleName;
     mixin("import " ~ moduleName!T ~ ";");
     mixin("alias ModuleOf = " ~ moduleName!T ~ ";");
}

can be used to qualify any function with the module in which one expects to find it.


 > Complexity ramps up further if there are N arguments to the algorithm.
 > It needs to search each of the arguments modules.

Bluntly, if a library is designed around multi-argument ADL as a core 
requirement, redesign it. I.e. the same advice as for multiple inheritance. It's 
just not worth it.

If you are still determined to use it, you can use:

    __traits(compiles, ...)

like you would SFINAE in C++ to select which of the modules from the argument 
types selects a function that compiles.