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[Steven Schveighoffer via Digitalmars-d]

On 11/14/15 3:42 AM, Dmitry Olshansky wrote:
> On 14-Nov-2015 02:10, Andrei Alexandrescu wrote:

>> * Lines 141-152: I couldn't make tail() work with inout. Generally I'm
>> very unhappy about inout. I don't know how to use it. Everything I read
>> about it is extremely complicated compared to its power. I wish we
>> removed it from the language and replaced it with an understandable
>> idiom.
>>
>
> I can't agree more. Every time dealing with inout when I finally think I
> grok how it works the next instant I see that it doesn't do what I expect.
>
> For me inout inevitably stops at the boundary of being unnable to have
> List!(inout(T)) and the like.

One thing we could allow is types that contain inout member variables, 
but ONLY in the context of inout functions. In other words, you can 
create a type for it, but can only use it in the context of an inout 
function.

A List!(inout(T)) outside an inout function has no meaning. This is why 
we disallowed it.

However, my belief is that it's the lack of a mechanism to apply an 
attribute to the tail of some struct that prevents the most utility 
here. If you returned a List!(inout(T)) there is no way to magically 
convert it to a List!(const(T)) or List!(immutable(T)).

Consider that Node in this code has a "const(Node)* next" as its tail.

I believe we should be able to achieve both.

-Steve