Portability	portable
Stability	experimental
Maintainer	libraries@haskell.org

Data.Int

Contents

Signed integer types
Notes

Description

Signed integer types

Synopsis

Signed integer types

data Int Source

A fixed-precision integer type with at least the range [-2^29 .. 2^29-1]. The exact range for a given implementation can be determined by using Prelude.minBound and Prelude.maxBound from the Prelude.Bounded class.

Instances

Bounded Int
Enum Int
Eq Int
Integral Int
Data Int
Num Int
Ord Int
Read Int
Real Int
Show Int
Ix Int
Typeable Int
Generic Int
Bits Int
Storable Int
PrintfArg Int

data Int8 Source

8-bit signed integer type

Instances

Bounded Int8
Enum Int8
Eq Int8
Integral Int8
Data Int8
Num Int8
Ord Int8
Read Int8
Real Int8
Show Int8
Ix Int8
Typeable Int8
Bits Int8
Storable Int8
PrintfArg Int8

data Int16 Source

16-bit signed integer type

Instances

Bounded Int16
Enum Int16
Eq Int16
Integral Int16
Data Int16
Num Int16
Ord Int16
Read Int16
Real Int16
Show Int16
Ix Int16
Typeable Int16
Bits Int16
Storable Int16
PrintfArg Int16

data Int32 Source

32-bit signed integer type

Instances

Bounded Int32
Enum Int32
Eq Int32
Integral Int32
Data Int32
Num Int32
Ord Int32
Read Int32
Real Int32
Show Int32
Ix Int32
Typeable Int32
Bits Int32
Storable Int32
PrintfArg Int32

data Int64 Source

64-bit signed integer type

Instances

Bounded Int64
Enum Int64
Eq Int64
Integral Int64
Data Int64
Num Int64
Ord Int64
Read Int64
Real Int64
Show Int64
Ix Int64
Typeable Int64
Bits Int64
Storable Int64
PrintfArg Int64

Notes

All arithmetic is performed modulo 2^n, where n is the number of bits in the type.
For coercing between any two integer types, use Prelude.fromIntegral, which is specialized for all the common cases so should be fast enough. Coercing word types (see Data.Word) to and from integer types preserves representation, not sign.
The rules that hold for Prelude.Enum instances over a bounded type such as Int (see the section of the Haskell report dealing with arithmetic sequences) also hold for the Prelude.Enum instances over the various Int types defined here.
Right and left shifts by amounts greater than or equal to the width of the type result in either zero or -1, depending on the sign of the value being shifted. 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.