C++ pointer templates

The smart pointer template library provides many different pointer templates. Each template is a different combination of features.

COPY SEMANTICS

The most salient feature of the pointer template is how the pointer is copied, (by the assignment operator or copy constructor). The three options are

• RefCount - the pointers share the same object and a reference count is used to determine when to destruct the object.

• OneOwner - the source pointer is set to NULL during copy so that never more than one pointer can point to the object.

• DeepCopy - when the pointer is copied, the object is also copied.

ARRAY SUPPORT

A pointer may point to only one object, or it may access an array of objects. Various levels of array support are available.

• None - array operations are not implemented

• FastArray - uses fast inline methods with no bounds checking

• SafeArray - check bounds on each array access

• Stack - checks bounds and can grow dynamically

PRIMITIVE TYPES

If the pointer template declares operator->, then the pointer cannot point to primitives, like char, long, double. Therefore this operator is optional.

FORWARD CLASSES

A pointer can point to a class T that is as yet undefined with one condition: the pointer destructor must not be inline. In this case the destructor can be defined in the .cpp after T is defined.

COMPARATOR OPERATORS

It may be useful if the operations <, >, <=, >=, == on the pointer would be delegated to the object. This way the pointers can be kept in a sorted collection of some kind. A macro is supplied to define these operators; they are not class methods.

The following is a list of all the template classes

• RefCountPointer

• RefCount1Pointer

• RefCountFwdPointer

• RefCountFwd1Pointer

• RefCountPrimPointer

• RefCountPrim1Pointer

• OneOwnerPointer

• OneOwner1Pointer

• OneOwnerFwdPointer

• OneOwnerFwd1Pointer

• OneOwnerPrimPointer

• OneOwnerPrim1Pointer

• DeepCopyPointer

• DeepCopy1Pointer

• DeepCopyPrimPointer

• DeepCopyPrim1Pointer

The templates with "Prim" in the name do not define operator->.

The templates with "Fwd" in the name do not define the destructor. The developer must explicitly define the destructor at the right place in the code using this macro

• DefinePointerDestructor( pointer-template, type )

The templates with "1" in the name do NOT declare any array operations such as operator[] and length. The templates without "1" in the name do declare the array operations, but they do not define them. The user may define the array operations with one and only one of the following macros

• DefinePointerFastArrayOps( scope, pointer-template, type )

• DefinePointerSafeArrayOps( scope, pointer-template, type )

• DefinePointerStackOps( scope, pointer-template, type )

Support for comparators can be added to any pointer template with the following macro

• DefinePointerComparators( scope, pointer-template )

In conclusion, the library provides 16 basic pointer templates, and 8 of them can have one of three array implementations, and comparators can be added to any template. That makes 64 combinations.

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