[Development] RFC: Proposal for a semi-radical change in Qt APIs taking strings

[Matthew Woehlke]

On 2015-10-14 07:15, Knoll Lars wrote:
> In addition, it might be tricky to use QStringView in signals and
> slots.

As I previously stated, I'm pretty sure you *CAN'T* use QStringView to
call slots, except for direct call. In any other case, you risk the
backing data being modified or, worse, deallocated, before the slot
dispatches (this is *especially* dangerous with cross-thread dispatch,
since now you have thread safety to worry about). The only way around
that would be for QStringView to take a COW reference to the underlying
data.

We already have a class like that. It's called QString.

What *might* work is if the event dispatcher, when it makes copies of
the arguments, makes a deep copy of QStringView into a QString. I'm not
sure if this is possible, though, and anyway then you're in the same
boat of making a (potentially) unnecessary deep copy if you had a
QString in the first place.

-- 
Matthew