Code behaves incorrectly if it is compiled in std.functional

[Mafi via Digitalmars-d]

On Friday, 5 June 2015 at 16:26:34 UTC, ketmar wrote:
> On Fri, 05 Jun 2015 15:17:50 +0000, Mafi wrote:
>
>> auto int x  = 10;
>> 
>> should work. It's just consistent.
>
> then `auto auto` should work too. it's a "declaration mark" + 
> "storage
> class".

Well, no. Any storage class marks a declaration just by itself. 
You don't use it as a "declaration mark" or "storage class", just 
use a storage class which definitely declares something new. See 
also http://dlang.org/declaration.html

A declaration is either <StorageClasses(opt) BasicType 
Declarators> or <AutoDeclaration>. An AutoDeclaration is the one 
with type inference. And it is marked by any storage class, not 
just auto (http://dlang.org/declaration.html#AutoDeclaration): 
<StorageClasses AutoDeclarationX>. Well admittently 
http://dlang.org/declaration.html#StorageClass does not feature 
'auto' as a storage class but this must be an error because the 
description of AutoDeclaration uses 'auto' in the place of 
StorageClasses.

It is just about grammar. A declaration needs a type, a storage 
class or both to not be mistaken for a statement with an assign 
expression. You use the 'auto' storage class so the statement 
cannot possibly be an expression when leaving out the type and 
not using any meaningful storage class.