Fallback 'catch-all' template functions

[Manu via Digitalmars-d]

On 3 September 2016 at 22:24, Andrei Alexandrescu via Digitalmars-d
<digitalmars-d at puremagic.com> wrote:
> On 9/3/16 7:29 AM, Manu via Digitalmars-d wrote:
>>
>> On 3 September 2016 at 11:38, Andrei Alexandrescu via Digitalmars-d
>> <digitalmars-d at puremagic.com> wrote:
>>>
>>> On 9/3/16 2:41 AM, Manu via Digitalmars-d wrote:
>>>>
>>>>
>>>> On 3 September 2016 at 00:18, Xinok via Digitalmars-d
>>>> <digitalmars-d at puremagic.com> wrote:
>>>>>
>>>>>
>>>>>
>>>>> In the past, I have suggested using the "default" keyword to specify a
>>>>> fallback function of this kind. I think it's a useful pattern for
>>>>> generic
>>>>> algorithms that have optimized variants on specific types for
>>>>> performance.
>>>>>
>>>>>    void f(T)(T t) if(isSomething!T) {}
>>>>>    void f(T)(T t) if(isSomethingElse!T) {}
>>>>>    void f(T)(T t) default {}
>>>>
>>>>
>>>>
>>>> It's an interesting idea... flesh out a DIP?
>>>
>>>
>>>
>>> We're better off without that. -- Andrei
>>
>>
>> Then we need a decent way to do this.
>
>
> Use static if inside the function. The entire notion of "call this function
> if you can't find something somewhere that works" is questionable. -- Andrei

It's all about: generic function 'lerp()' exists... user supplies new
type, user extends standard named function 'lerp()' for their new
type.
We do this sort of things a lot. Consider std.conv.to?