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This patch implements mozilla::NotNull, which is similar but not identicial to gsl::not_null. The current draft(?) implementation of gsl::not_null is at https://github.com/Microsoft/GSL/blob/master/include/gsl.h. The main difference is that not_null allows implicit conversion from T to not_null<T>. In contrast, NotNull only allows explicit conversion from T to NotNull<T> via WrapNotNull(). The rationale for this is that when converting from a less-constrained type to a more constrained type, implicit conversion is undesirable. For example, if I changed a function f from this: f(int* aPtr); to this: f(gsl::not_null<int*> aPtr); no call sites would have to be modified. But if I changed it to this: f(mozilla::NotNull<int*> aPtr); call sites *would* need to be modified. This is a good thing! It forces the author to audit the call sites for non-nullness, and encourages them to back-propagate NotNull throughout the code. The other difference between not_null and NotNull is that not_null disables pointer arithmetic, which means it cannot be used with array pointers. I have not implemented this restriction for NotNull because it seems arbitrary and unnecessary. |
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| .. | ||
| decimal | ||
| double-conversion | ||
| staticruntime | ||
| tests | ||
| Alignment.h | ||
| AllocPolicy.h | ||
| AlreadyAddRefed.h | ||
| Array.h | ||
| ArrayUtils.h | ||
| Assertions.h | ||
| Atomics.h | ||
| Attributes.h | ||
| BinarySearch.h | ||
| BloomFilter.h | ||
| BufferList.h | ||
| Casting.h | ||
| ChaosMode.cpp | ||
| ChaosMode.h | ||
| Char16.h | ||
| CheckedInt.h | ||
| Compiler.h | ||
| Compression.cpp | ||
| Compression.h | ||
| DebugOnly.h | ||
| EndianUtils.h | ||
| EnumeratedArray.h | ||
| EnumeratedRange.h | ||
| EnumSet.h | ||
| FastBernoulliTrial.h | ||
| FloatingPoint.cpp | ||
| FloatingPoint.h | ||
| Function.h | ||
| GuardObjects.h | ||
| HashFunctions.cpp | ||
| HashFunctions.h | ||
| IndexSequence.h | ||
| InitializerList.h | ||
| IntegerPrintfMacros.h | ||
| IntegerRange.h | ||
| IntegerTypeTraits.h | ||
| JSONWriter.cpp | ||
| JSONWriter.h | ||
| Likely.h | ||
| LinkedList.h | ||
| LinuxSignal.h | ||
| lz4.c | ||
| lz4.h | ||
| MacroArgs.h | ||
| MacroForEach.h | ||
| MathAlgorithms.h | ||
| Maybe.h | ||
| MaybeOneOf.h | ||
| MemoryChecking.h | ||
| MemoryReporting.h | ||
| Move.h | ||
| moz.build | ||
| NotNull.h | ||
| NullPtr.h | ||
| NumericLimits.h | ||
| objs.mozbuild | ||
| Opaque.h | ||
| Pair.h | ||
| PodOperations.h | ||
| Poison.cpp | ||
| Poison.h | ||
| Range.h | ||
| RangedArray.h | ||
| RangedPtr.h | ||
| ReentrancyGuard.h | ||
| RefCounted.h | ||
| RefCountType.h | ||
| RefPtr.h | ||
| ReverseIterator.h | ||
| RollingMean.h | ||
| Saturate.h | ||
| Scoped.h | ||
| ScopeExit.h | ||
| SegmentedVector.h | ||
| SHA1.cpp | ||
| SHA1.h | ||
| SizePrintfMacros.h | ||
| Snprintf.h | ||
| SplayTree.h | ||
| STYLE | ||
| TaggedAnonymousMemory.cpp | ||
| TaggedAnonymousMemory.h | ||
| TemplateLib.h | ||
| ThreadLocal.h | ||
| ToString.h | ||
| Tuple.h | ||
| TypedEnumBits.h | ||
| Types.h | ||
| TypeTraits.h | ||
| UniquePtr.h | ||
| UniquePtrExtensions.h | ||
| unused.cpp | ||
| unused.h | ||
| Variant.h | ||
| Vector.h | ||
| WeakPtr.h | ||
| WindowsVersion.h | ||
| XorShift128PlusRNG.h | ||