Native Types - C++

NATIVE TYPES

  bool

  char, wchar_t

o   modified with signed or unsigned

int

o modified with signed or unsigned o can be modified with short or long o int can be dropped! long num;

o   can be modified with const or volatile

Native C++ Types: Bottom Line

float 

double  long double

bool

char

int     unsigned long

float double

pitfalls

Type Size

Language standard does not define the size of native types sizeof(type) operator

limits.h and float.h

o Defines the largest and smallest type values include <limits>

o   numeric_limits<type>::max()

1. Implicit conversions (coercion)

Occur in mixed expressions Widening conversions:

int < unsigned < long < unsigned long < float < double < long double Widening safe, narrowing unsafe.

But: narrowing conversions allowed with assignments

2. Enumeration Types

Named integer constants

enum Animal {Cat, Dog, Horse = 5}; Tag name, enumerators must be unique Implicit conversion to integer

int i = Dog; // assigns 1 to i

Explicit cast from integer

y Animal anim = static_cast<Animal>i; C++ trick:

enum {SIZE = 100}; replaces #define SIZE 100