auto return for some recursive functions in C++11

[MattCoder via Digitalmars-d]

On Wednesday, 14 January 2015 at 22:29:09 UTC, bearophile wrote:
> According to Wikipedia:
> http://en.wikipedia.org/wiki/C%2B%2B14#Function_return_type_deduction
>
> C++14 is able to compile code like this:
>
>
> auto correct(int i) {
>     if (i == 1)
>         return i;
>     else
>         return correct(i - 1) + i;
> }
> ...

According to the wiki link:

"If multiple return expressions are used in the function's
implementation, then they must all deduce the same type."

So this will NOT work:

auto Correct(int i) {
      if (i == 1){
          return (int)5;
      }else{
          return (float)10;
      }
}

Error:

prog.cpp: In function 'auto Correct(int)':
prog.cpp:8:19: error: inconsistent deduction for 'auto': 'int'
and then 'float'
       return (float)10;
                     ^

So could you please tell me a good use case to for using "return
type deduction"?

Matheus.