Basic +Types Overview

Description

The API defines classes and typedefs +for integer, text, Boolean, and floating point types. Additionally, a utility +class to help with reference arguments in variable argument functions is provided.

Heap-allocated classes base

Symbian platform requires that +all classes that own dynamically allocated resources derive from a standard +base class, CBase. Such classes by conventions have a C +prefix to their name, and so are referred to as C classes. C classes, and +their associated allocation and cleanup idioms, are fundamental to Symbian +platform.

Integral +types

TInt is the natural machine word integer +and should be used in all general contexts where integer arithmetic is desired.

TInt32, TInt16 and TInt8 map onto C++ built-in types in most implementations. These +types should only be used where the size of the integer is of first importance.

TUint is +an unsigned integer of the natural machine word size. It should be used for +flag and handle words, which are manipulated using bitwise and equality-comparison +operations rather than arithmetic.

TUint32, TUint16 and TUint8 are +available where the specific representation width is important.

Text types

TText represents a character +in the natural width for the Symbian platform build. From v5.1 onwards, this +is 16 bits.

TText8 is available for build-independent +8-bit characters, and TText16 for build-independent 16-bit +characters.

The TChar class wraps a character value +and provides a number of utility functions to operate upon it.

Boolean type

TBool represents a Boolean +whose value may be true or false. It is implemented as a natural machine-word +integer.

Floating-point +types

TReal is a 64-bit double-precision type, +used as the argument type for all math functions, and the default type of +floating-point literals.

TReal64 and TReal32 are +available when the precise size is important.

Value reference type

The value reference type is a utility +that is provided to overcome problems with specifying a C++ reference argument +before the ellipsis argument in variable argument functions.

The value +reference type is provided by TRefByValue <T>.

Global functions

Max(), Min(), Rng() and Abs() are simple global +functions that are useful in many contexts.