The Converter class, in the eponymous example, had a null member
variable that wasn't a nullptr - it pointed to an instance of
NullConverter - so that other converters could test whether a
Converter * they'd been passed was null (in the sense of pointing to a
NullConverter). This, however, was susceptible to misreading - I
misread one such comparison as a nullptr check and thus thought it
redundant with an earlier actual nullptr check. To spare future
readers similar confusion, replace the public static member variable
with a protected (since only other derived classes need it) static
predicate, to at least give the reader a clue that this is using the
word null in a class-specific sense.
Pick-to: 6.5
Task-number: QTBUG-111228
Change-Id: I1e4f494b303d1bf90107f8c6fa3a4a22f6d81b90
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
(cherry picked from commit 0b1670134b43ba390f35b52d2458e4269a804de3)
Reviewed-by: Qt Cherry-pick Bot <cherrypick_bot@qt-project.org>
2eb1a72f73