D constrains integral types to specific sizes. But efficiency
of different sizes varies from machine to machine,
pointer sizes vary, and the maximum integer size varies.
<b>stdint</b> offers a portable way of trading off size
vs efficiency, in a manner compatible with the <tt>stdint.h</tt>
definitions in C.

In the table below, the exact aliases are types of exactly the
specified number of bits.
The at least aliases are at least the specified number of bits
large, and can be larger.
The fast aliases are the fastest integral type supported by the
processor that is at least as wide as the specified number of bits.

The aliases are:

Exact Alias

Description

At Least Alias

Description

Fast Alias

Description

int8_t

exactly 8 bits signed

int_least8_t

at least 8 bits signed

int_fast8_t

fast 8 bits signed

uint8_t

exactly 8 bits unsigned

uint_least8_t

at least 8 bits unsigned

uint_fast8_t

fast 8 bits unsigned

int16_t

exactly 16 bits signed

int_least16_t

at least 16 bits signed

int_fast16_t

fast 16 bits signed

uint16_t

exactly 16 bits unsigned

uint_least16_t

at least 16 bits unsigned

uint_fast16_t

fast 16 bits unsigned

int32_t

exactly 32 bits signed

int_least32_t

at least 32 bits signed

int_fast32_t

fast 32 bits signed

uint32_t

exactly 32 bits unsigned

uint_least32_t

at least 32 bits unsigned

uint_fast32_t

fast 32 bits unsigned

int64_t

exactly 64 bits signed

int_least64_t

at least 64 bits signed

int_fast64_t

fast 64 bits signed

uint64_t

exactly 64 bits unsigned

uint_least64_t

at least 64 bits unsigned

uint_fast64_t

fast 64 bits unsigned

The ptr aliases are integral types guaranteed to be large enough
to hold a pointer without losing bits:

Alias

Description

intptr_t

signed integral type large enough to hold a pointer

uintptr_t

unsigned integral type large enough to hold a pointer

D constrains integral types to specific sizes. But efficiency of different sizes varies from machine to machine, pointer sizes vary, and the maximum integer size varies. <b>stdint</b> offers a portable way of trading off size vs efficiency, in a manner compatible with the <tt>stdint.h</tt> definitions in C.

In the table below, the

exact aliases are types of exactly the specified number of bits. Theat least aliases are at least the specified number of bits large, and can be larger. Thefast aliases are the fastest integral type supported by the processor that is at least as wide as the specified number of bits.The aliases are:

The ptr aliases are integral types guaranteed to be large enough to hold a pointer without losing bits:

The max aliases are the largest integral types: