Automatic variable declaration

[ixid]

On Wednesday, 15 August 2018 at 14:58:40 UTC, Everlast wrote:
> Many times one must create a variable before a function call:
>
>
>   int x = 3;
>   foo(x);
>   writeln(x);
>
> and this is fraught with problems such as dependencies(move or 
> change the second line and one has to validate how the first 
> line is affected along with all the others).
>
> A new an improved technique, which consolidates the two lines 
> in to one is to automatically have the compiler define the 
> variable:
>
> foo(x = 3);
> writeln(x); // x was implicitly created in this scope by foo.

Couldn't you do what you need to do with UFCS and possibly a tee 
function if you need to add things like writeln into the chain 
that don't pass the data on?