Use case for std.bind

[Lars Kyllingstad]

Daniel Keep wrote:
> 
> Lars Kyllingstad wrote:
>> [snip]
>>
>> I for one like it, and would very much like to see such a syntax in D2.
>> Also, I'd have it work with either of a function's arguments, not only
>> the leading or trailing ones:
>>
>>   int foo(int a, int b, int c, int d) {...}
>>   auto bar1 = foo(_, b, c, d);
>>   auto bar2 = foo(a, b, c, _);
>>   auto bar3 = foo(_, b, _, d);
>>
>>   assert (is (typeof(bar3) == int delegate(int, int)));
>>
>> In its simplest form, it would just be syntactic sugar for the delegate
>> literal. But I'm curious: If foo is a pure function, couldn't the
>> compiler perform some extra optimization here?
>>
>> -Lars
> 
> auto a = b(_, c(_, x), _);
> 
> What are the types of a, b and c?  What if b has multiple overloads or
> is templated?
> 
> Context-dependant grammar (let alone context-dependant single character
> symbols): just say "no".
> 
>   -- Daniel

Good point. How about this alternative syntax, then:

   auto bar3 = foo(int, b, int, d);

Will this also cause problems?

-Lars