What is the correct use of auto?

[Tower Ty]

Steven Schveighoffer Wrote:

> "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?
> 
> The best reason for auto is maintainability.
> 
> If you decide to change what some function returns, then you have to go 
> through all your code and change the return type in all places it is used. 
> If you use auto, it's already done :)  Most frequent thing that happens to 
> me is, I find I've declared something as returning int, and realize it 
> really should have been uint.
> 
> The second best reason is for template instantiation:
> 
> TemplateClass!(int, string, 5) variable = new TemplateClass!(int, string, 
> 5);
> vs.
> auto variable = new TemplateClass!(int, string, 5);
> There's also a maintainability aspect to that as well, if you decide to 
> change the template type.
> 
> I've spottily used auto, and I've found in many cases that I wished I had 
> used it everywhere :)  seldom does it hurt you to use it, and it's usually 
> pretty clear what it means.
> 
> -Steve 
> 
> 
Steven Schveighoffer Wrote:


> If you decide to change what some function returns, then you have to go 
> through all your code and change the return type in all places it is used. 
> If you use auto, it's already done :)  Most frequent thing that happens to 
> me is, I find I've declared something as returning int, and realize it 
> really should have been uint.
> 
> The second best reason is for template instantiation:
> 
> TemplateClass!(int, string, 5) variable = new TemplateClass!(int, string, 
> 5);
> vs.
> auto variable = new TemplateClass!(int, string, 5);
> There's also a maintainability aspect to that as well, if you decide to 
> change the template type.
> 
> I've spottily used auto, and I've found in many cases that I wished I had 
> used it everywhere :)  seldom does it hurt you to use it, and it's usually 
> pretty clear what it means.
> 
> -Steve 

Ive just read through all the souffle , and somethingelse  and beercans and underwear type answers here which are just pure time wasting crap. 

The above is the first answer that is informative , readable and understandable -Thanks Steve