return a QVariantList

[ggdev001]

Hi,

it is not ok to return a QVariantList variable from a function right?

e.g.,

QVariantList app::f()
{
QVariantList obj;
return obj;
}

QVariantList app::f()
{
QVariantList obj;
return obj;
}

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because obj will go out of scope when f exits?? (ps.I understand this maybe common to all data types, just checking).

[lanz]

No, it's OK, because here obj is being returned by value(i.e. a copy of obj will be created and then returned).

You shouldn't do this only if value is returned by reference, for example:

QVariantList &app::f ()
{
   QVariantList obj;
   ///WRONG!
   return obj;
}

QVariantList &app::f ()
{
   QVariantList obj;
   ///WRONG!
   return obj;
}

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[ggdev001]

Yes I also think it is ok in general to return QList QMap or any other data type.

I think problematic also next to what you mentioned is if I am supposed to return a pointer from a function and I return
a pointer to a local variable (e.g., int x) that was defined inside the function.