# Data.Word

#### Description

Unsigned integer types.

## Unsigned integral types

data Word :: * Source

A Word is an unsigned integral type, with the same size as Int.

#### Instances

 Bounded Word Enum Word Eq Word Integral Word Data Word Num Word Ord Word Read Word Real Word Show Word Ix Word FiniteBits Word Bits Word Storable Word PrintfArg Word

data Word8 Source

8-bit unsigned integer type

#### Instances

 Bounded Word8 Enum Word8 Eq Word8 Integral Word8 Data Word8 Num Word8 Ord Word8 Read Word8 Real Word8 Show Word8 Ix Word8 FiniteBits Word8 Bits Word8 Storable Word8 PrintfArg Word8

data Word16 Source

16-bit unsigned integer type

#### Instances

 Bounded Word16 Enum Word16 Eq Word16 Integral Word16 Data Word16 Num Word16 Ord Word16 Read Word16 Real Word16 Show Word16 Ix Word16 FiniteBits Word16 Bits Word16 Storable Word16 PrintfArg Word16

data Word32 Source

32-bit unsigned integer type

#### Instances

 Bounded Word32 Enum Word32 Eq Word32 Integral Word32 Data Word32 Num Word32 Ord Word32 Read Word32 Real Word32 Show Word32 Ix Word32 FiniteBits Word32 Bits Word32 Storable Word32 PrintfArg Word32

data Word64 Source

64-bit unsigned integer type

#### Instances

 Bounded Word64 Enum Word64 Eq Word64 Integral Word64 Data Word64 Num Word64 Ord Word64 Read Word64 Real Word64 Show Word64 Ix Word64 FiniteBits Word64 Bits Word64 Storable Word64 PrintfArg Word64

## byte swapping

Swap bytes in Word16.

Since: 4.7.0.0

Reverse order of bytes in Word32.

Since: 4.7.0.0

Reverse order of bytes in Word64.

Since: 4.7.0.0

## Notes

• All arithmetic is performed modulo 2^n, where n is the number of bits in the type. One non-obvious consequence of this is that negate should not raise an error on negative arguments.
• For coercing between any two integer types, use fromIntegral, which is specialized for all the common cases so should be fast enough. Coercing word types to and from integer types preserves representation, not sign.
• An unbounded size unsigned integer type is available with Natural.
• The rules that hold for Enum instances over a bounded type such as Int (see the section of the Haskell report dealing with arithmetic sequences) also hold for the Enum instances over the various Word types defined here.
• Right and left shifts by amounts greater than or equal to the width of the type result in a zero result. This is contrary to the behaviour in C, which is undefined; a common interpretation is to truncate the shift count to the width of the type, for example 1 << 32 == 1 in some C implementations.

© The University of Glasgow and others