[Development] QList
Thiago Macieira
thiago.macieira at intel.com
Tue Apr 25 21:35:01 CEST 2017
On Tuesday, 25 April 2017 15:45:12 -03 Matthew Woehlke wrote:
> Maybe an alternate approach makes sense?
>
> 1. Rename QList -> QArrayList.
> 2. Remove special case of inline storage.
> 3. Add QList<T> as an alias to either QArrayList<T> or QVector<T>
> depending on T.
QVector and QList don't have the same API. They're slightly different. What'sm
ore, QList has a beginning-of-list optimisation, whereas QVector doesn't (not
even my copy, I stopped development shortly before I got to that part, even if
I did add a QArrayData::GrowsBackward flag to support the case).
Also note that QList<char> is different from QVector<char>. QList<T> would
need to be backed by QVector<quintptr> and a proper casting.
We can't use an alias either, we'd need a full class, with constructors,
destructors, etc., to keep binary compatibility. And I don't think we can keep
data compatibility, as QList's internals are very different from QVector's
(different shared_null, different allocation strategies, different
deallocation function, etc.).
So, no, we can't implement that in Qt 5. In Qt 6, we've already agreed we
don't want this mess, so QList as it is simply goes away.
--
Thiago Macieira - thiago.macieira (AT) intel.com
Software Architect - Intel Open Source Technology Center
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