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# std.stdint

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. stdint offers a portable way of trading off size vs efficiency, in a manner compatible with the `stdint.h` 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

The max aliases are the largest integral types:

Alias | Description
--- | ---
intmax_t | the largest signed integral type
uintmax_t | the largest unsigned integral type

License:
Boost License 1.0.
Authors:
Walter Bright

Source std/stdint.d

Copyright © 1999-2021 by the D Language Foundation | Page generated by Ddoc on Thu Feb 18 11:53:39 2021