UnliftIO.Foreign

The Bits class defines bitwise operations over integral types.

• Bits are numbered from 0 with bit 0 being the least significant bit.

Default implementation for bit.

Note that: bitDefault i = 1 shiftL i

Default implementation for popCount.

This implementation is intentionally naive. Instances are expected to provide an optimized implementation for their size.

Default implementation for testBit.

Note that: testBitDefault x i = (x .&. bit i) /= 0

Attempt to convert an Integral type a to an Integral type b using the size of the types as measured by Bits methods.

A simpler version of this function is:

toIntegral :: (Integral a, Integral b) => a -> Maybe b
toIntegral x
  | toInteger x == toInteger y = Just y
  | otherwise                  = Nothing
  where
    y = fromIntegral x

This version requires going through Integer, which can be inefficient. However, toIntegralSized is optimized to allow GHC to statically determine the relative type sizes (as measured by bitSizeMaybe and isSigned) and avoid going through Integer for many types. (The implementation uses fromIntegral, which is itself optimized with rules for base types but may go through Integer for some type pairs.)

Infix version of unsafeShiftL.

Infix version of unsafeShiftR.

Infix version of shiftL.

Infix version of shiftR.

Infix version of xor.

A more concise version of complement zeroBits.

>>> complement (zeroBits :: Word) == (oneBits :: Word)True

>>> complement (oneBits :: Word) == (zeroBits :: Word)True

Note

The constraint on oneBits is arguably too strong. However, as some types (such as Natural) have undefined complement, this is the only safe choice.

The FiniteBits class denotes types with a finite, fixed number of bits.

Monoid under bitwise AND.

>>> getAnd (And 0xab <> And 0x12) :: Word82

Monoid under bitwise 'equality'; defined as 1 if the corresponding bits match, and 0 otherwise.

>>> getIff (Iff 0xab <> Iff 0x12) :: Word870

Monoid under bitwise inclusive OR.

>>> getIor (Ior 0xab <> Ior 0x12) :: Word8187

Monoid under bitwise XOR.

>>> getXor (Xor 0xab <> Xor 0x12) :: Word8185

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.

64-bit signed integer type

32-bit signed integer type

16-bit signed integer type

8-bit signed integer type

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

64-bit unsigned integer type

32-bit unsigned integer type

16-bit unsigned integer type

8-bit unsigned integer type

Reverse the order of the bits in a Word16.

Reverse the order of the bits in a Word32.

Reverse the order of the bits in a Word64.

Reverse the order of the bits in a Word8.

Reverse order of bytes in Word16.

Reverse order of bytes in Word32.

Reverse order of bytes in Word64.

Haskell type representing the C int type. (The concrete types of Foreign.C.Types#platform are platform-specific.)

Haskell type representing the C bool type. (The concrete types of Foreign.C.Types#platform are platform-specific.)

Haskell type representing the C char type. (The concrete types of Foreign.C.Types#platform are platform-specific.)

Haskell type representing the C clock_t type. (The concrete types of Foreign.C.Types#platform are platform-specific.)

Haskell type representing the C double type. (The concrete types of Foreign.C.Types#platform are platform-specific.)

Haskell type representing the C FILE type. (The concrete types of Foreign.C.Types#platform are platform-specific.)

Haskell type representing the C float type. (The concrete types of Foreign.C.Types#platform are platform-specific.)

Haskell type representing the C fpos_t type. (The concrete types of Foreign.C.Types#platform are platform-specific.)

Haskell type representing the C jmp_buf type. (The concrete types of Foreign.C.Types#platform are platform-specific.)

Haskell type representing the C long long type. (The concrete types of Foreign.C.Types#platform are platform-specific.)

Haskell type representing the C long type. (The concrete types of Foreign.C.Types#platform are platform-specific.)

Haskell type representing the C ptrdiff_t type. (The concrete types of Foreign.C.Types#platform are platform-specific.)

Haskell type representing the C signed char type. (The concrete types of Foreign.C.Types#platform are platform-specific.)

Haskell type representing the C suseconds_t type. (The concrete types of Foreign.C.Types#platform are platform-specific.)

Haskell type representing the C short type. (The concrete types of Foreign.C.Types#platform are platform-specific.)

Haskell type representing the C sig_atomic_t type. (The concrete types of Foreign.C.Types#platform are platform-specific.) See Note [Lack of signals on wasm32-wasi].

Haskell type representing the C size_t type. (The concrete types of Foreign.C.Types#platform are platform-specific.)

Haskell type representing the C time_t type. (The concrete types of Foreign.C.Types#platform are platform-specific.)

Haskell type representing the C unsigned char type. (The concrete types of Foreign.C.Types#platform are platform-specific.)

Haskell type representing the C unsigned int type. (The concrete types of Foreign.C.Types#platform are platform-specific.)

Haskell type representing the C unsigned long long type. (The concrete types of Foreign.C.Types#platform are platform-specific.)

Haskell type representing the C unsigned long type. (The concrete types of Foreign.C.Types#platform are platform-specific.)

Haskell type representing the C useconds_t type. (The concrete types of Foreign.C.Types#platform are platform-specific.)

Haskell type representing the C unsigned short type. (The concrete types of Foreign.C.Types#platform are platform-specific.)

Haskell type representing the C wchar_t type. (The concrete types of Foreign.C.Types#platform are platform-specific.)

A C string is a reference to an array of C characters terminated by NUL.

A string with explicit length information in bytes instead of a terminating NUL (allowing NUL characters in the middle of the string).

Lifted peekCString.

Lifted peekCStringLen.

Lifted newCString.

Lifted newCStringLen.

Unlifted withCString.

Unlifted withCStringLen.

Convert a Haskell character to a C character. This function is only safe on the first 256 characters.

Convert a C byte, representing a Latin-1 character, to the corresponding Haskell character.

Convert a Haskell character to a C unsigned char. This function is only safe on the first 256 characters.

Convert a C unsigned char, representing a Latin-1 character, to the corresponding Haskell character.

Convert a Haskell character to a C signed char. This function is only safe on the first 256 characters.

Convert a C signed char, representing a Latin-1 character, to the corresponding Haskell character.

Lifted peekCAString.

Lifted peekCAStringLen.

Lifted newCAString.

Lifted newCAStringLen.

Unlifted withCAString.

Unlifted withCAStringLen.

A C wide string is a reference to an array of C wide characters terminated by NUL.

A wide character string with explicit length information in CWchars instead of a terminating NUL (allowing NUL characters in the middle of the string).

Lifted peekCWString.

Lifted peekCWStringLen.

Lifted newCWString.

Lifted newCWStringLen.

Unlifted withCWString.

Unlifted withCWStringLen.

Haskell representation for errno values. The implementation is deliberately exposed, to allow users to add their own definitions of Errno values.