Purity, @safety, etc., in generic code

[Steven Schveighoffer]

On Wed, 20 Feb 2013 21:50:01 -0500, deadalnix <deadalnix at gmail.com> wrote:

> On Wednesday, 20 February 2013 at 13:42:48 UTC, Steven Schveighoffer  
> wrote:
>> On Wed, 20 Feb 2013 01:00:00 -0500, deadalnix <deadalnix at gmail.com>  
>> wrote:
>>
>>> As discussed previously, I really wonder hy a const and non const  
>>> version of a function can exists in a first place. What problem does  
>>> it solve that isn't better solved by inout ?
>>
>> const(T) and T are different types.  Saying you can overload on types,  
>> unless they just vary by const is a special case that I don't think is  
>> worth adding.
>>
>
> Explain me how the hell you overload on implicit parameter types ?

A method is simply a function that takes a hidden parameter of an object  
or struct.

Really, a method with a signature Obj.foo() is a function with a signature  
foo(Obj this)

A const method Obj.foo() const is a function with a signature  
foo(const(Obj) this)

So it's equivalent to saying you can overload:

foo(int *x)
foo(const(int) *x)

To disallow this would be unnecessarily restrictive.

-STeve