What is the correct use of auto?

[Hans W. Uhlig]

Unknown W. Brackets wrote:
> A great example is when using a library.  Instead of using a "void*" or 
> something like that, you'd use an auto.
> 
> Example:
> 
> auto valueType = library.getSomething();

I am coming from C and Java (sorry no C++), why wouldn't you declare a 
typed variable to store the class. Doesn't using auto introduce 
ambiguity to the compiler and the code itself.

And this is secondary but how would you use any form of autosense 
against this since its type can change from execution to execution.

> 
> auto souffle = library.makeSomethingSouffle(valueType);
> library.somethingElse(souffle);
> 

Again what is a souffle and why wouldnt you want it to be
Souffle mySouffle = library.makeSomethingSouffle(valueType); so that its 
properties are known at compile time.

> Another use is when a particular section of your code doesn't care about 
> the type, and you're just paper-pushing.  This way, even if you need to 
> change the type later, you don't have to revisit the code (just 
> recompile it.)

why bother to paper push if the value is unnecessary. Why not simply 
discard and move on?

> 
> It's also handy for this:
> 
> auto abc = new com.example.somethinglong.modulename.Package();
> 
> Although mostly you would use an alias for that anyway.
> 
> And that's not even mentioning templates, where it's very very useful.
> 
> -[Unknown]
> 
> 
> Hans W. Uhlig wrote:
>> I have been reading through the specification and playing with D more 
>> and more, what is the purpose of auto. I can understand in languages 
>> with scalar types handling datatypes on assignment but on a strictly 
>> typed language like C or D when would auto(as a variable declaration) 
>> provide more useful functionality then it removes from readability.
>>
>> When would this be useful rather then simply specifying the type?