- is not feasible for practical usage and (was up to now not used, thus no consequence)
moreover, Oersted is a cgs unit while we use SI units, thus also not suitable for FEM, only makes problems for magnetization
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Document provides a new functionality, to signal subscribed user code of messages intended for the user.
The main motivation is critical messages of broken forward compatibility during restoring a document into a new version of FreeCAD.
However, the framework may be used in many other ways.
Added new signal interface using boost::signals2 signalParamChanged.
Exposed to Python as ParameterGrpPy.AttachManager() to monitor changes
to all parameters, sub groups under the referring group.
Added new attribute for ParameterGrp(Py) to query the Parent and Manager
of the referring group.
* ignore -Wfree-nonheap-object for generated code
* replace 0 with Qt::NoModifier when creating a QKeyEvent
* in Qt 5.14 QCombobox::activated(QString) is deprecated, use textActivated
* don't mix QCheckBox::setChecked() with tristate API
Removes the BUILD_QT5 flag and adds a new FREECAD_QT_VERSION option,
which can be set to either "Auto" (default), 5, or 6. Auto detects which
version of Qt is installed on the system and chooses it. If both version
are installed, Qt5 is used.
Note that this DOES NOT implement compiling against Qt6, it only adds
the necessary cMake infrastructure to begin work on the source code
changes that will be required.
The problem is that inside Transaction::addObjectNew() a transaction object is deleted before removing it from the container. When deleting the corresponding transactional object (i.e. a DocumentObject or ViewProvider)
it can happen that it e.g. calls Transaction::addOrRemoveProperty() that now finds the dangling pointer in the container.
The safe way is to first remove the object from the container before deleting it.
