typeof(SortedRange) and is operator

[Ali Çehreli via Digitalmars-d-learn]

On 11/08/2016 07:06 AM, RazvanN wrote:

 >> `SortedRange!(int[], "a<b") == SortedRange!(int[], "a < b")` is false
 >> because the arguments to the templates differ i.e. "a<b" != "a < b".
 >>
 >> Is this a bug? no. is it weird, confusing and unintuitive? yes.
 >
 > I think that lambda comparison should be done logically (by that I mean:
 > what the function actually computes) not literally.

Still, from the point of view of the language string template parameters 
are not necessarily lambdas. The fact that a particular template may mix 
them in and use in similar fashion cannot change it.

 > For example: it is a
 > mistake to consider the 2 two lambda functions different just because
 > one expression has more white spaces.

Possibly but again, the language not necessarily knows what that string 
means. The whitespace my be significant.

 > Also "a < b" is the same lambda
 > function as "e < d"; considering these 2 functions to not be equal is a
 > mistake.

So-called "string lambdas" are actually pretty weird. You know that "e < 
d" cannot work with SortedRange, right? The string is actually mixed-in; 
so you have to know what the surrounding code expects and provide a 
matching string. In this case, you have to provide 'a' and 'b'.

Ali