Re: Unnecessary initialization in octave_matrix::double_value ?

[Julien Bect]

Le 28/08/2016 à 10:12, Julien Bect a écrit :
> Hi all,
>
> I have a (probably naive) C++ question concerning the implementation 
> of octave_matrix::double_value ().
>
> It is currently written like this:
>
> double
> octave_matrix::double_value (bool) const
> {
>   double retval = lo_ieee_nan_value ();
>
>   if (is_empty ())
>     err_invalid_conversion ("real matrix", "real scalar");
>
>   warn_implicit_conversion ("Octave:array-to-scalar",
>                             "real matrix", "real scalar");
>
>   retval = matrix(0, 0);
>
>   return retval;
> }
>
> I don't understand the point of initializing retval with the result of 
> lo_ieee_nan_value ().  Would it be correct to simply write:
>
> double
> octave_matrix::double_value (bool) const
> {
>   if (is_empty ())
>     err_invalid_conversion ("real matrix", "real scalar");
>
>   warn_implicit_conversion ("Octave:array-to-scalar",
>                             "real matrix", "real scalar");
>
>   return matrix (0, 0);
> }
>
> ?

One more thing: while grep for ::float_value and ::double_value, I 
noticed that all of them declare retval at the beginning, but only some 
of them initialize it with lo_ieee_nan_value (or lo_ieee_float_nan_value).

@++
Julien