Data.Repa.Scalar.Int

Loading and storing integers directly from/to memory buffers.

• The implementation uses native Haskell unboxed primitives. There there should not be any significant performance penalty relative to the standard implementations in other languages (like C).

Reading from strings

readInt :: String -> Maybe Int

Read an Int from a String, or Nothing if this isn't one.

readIntFromByteString :: ByteString -> Maybe Int

Read an Int from a ByteString, or Nothing if this isn't one.

Loading from buffers

loadInt

Arguments

:: Ptr Word8

Buffer holding digits.

-> Int

Length of buffer.

-> b

On convert failure, return this value.

-> (Int -> Int -> b)

On convert success, given int read and number of chars.

-> b

Load an ASCII Int from a foreign buffer, returning the value and number of characters read.

• This function is set to INLINE. It unboxes the pointer and integer then calls loadInt#, which is NOINLINE.

loadInt#

Arguments

:: Addr#

Address of buffer holding digits

-> Int#

Length of buffer.

-> (#Int#, Int#, Int##)

Convert success?, value, length read.

Load an ASCII Int from a buffer, producing an unboxed tuple describing the result.

• This function is set to NOINLINE, so it can be safely called from multiple places in the program.

loadIntWith#

Arguments

:: Int#

Length of input buffer.

-> (Int# -> Int#)

Function to get a byte from the source.

-> (#Int#, Int#, Int##)

Convert success?, value, length read

Primitive Int loading function.

• This function is set to INLINE, so you will get a new copy of it in the compiled program each time it is invoked. Consider providing an appropriate wrapper for your use case.

Showing to strings

Unpadded

showInt :: Int -> String

Show an Int, allocating a new String.

showIntToByteString :: Int -> ByteString

Show an Int, allocating a new ByteString.

Padded

showIntPad :: Int -> Int -> String

Show an Int, allocating a new String.

showIntPadToByteString :: Int -> Int -> ByteString

Show an Int, allocating a new ByteString.

Storing to buffers

Unpadded

storeInt

Arguments

:: Ptr Word8

Pointer to output buffer.

-> Int

Int to store.

-> IO Int

Number of bytes written.

Store an ASCII Int into a buffer, producing the number of bytes written.

• This functon is set to INLINE. It unboxes the pointer and integer then calls storeInt# which is NOINLINE.

storeInt#

Arguments

:: Addr#

Address of output buffer.

-> Int#

Int to store.

-> IO Int

Number of bytes written.

Store an ASCII Int into a buffer, producing the number of bytes written.

• This function is set to NOINLINE, so it can be safely called from multiple places in the program.

storeIntWith#

Arguments

:: (Int# -> IO buf)

Function to allocate a new output buffer, given the length in bytes.

-> (buf -> Int# -> Int# -> IO ())

Function to write a byte to the buffer, given the index and byte value.

-> Int#

Int to store.

-> (buf -> Int# -> IO b)

Continuation for buffer and bytes written.

-> IO b

Primitive Int storing function.

• This function is set to INLINE, so you will get a new copy of it in the compiled program each time it is invoked. Consider providing an appropriate wrapper for your use case.

Padded

storeIntPad

Arguments

:: Ptr Word8

Pointer to output buffer.

-> Int

Int to store.

-> Int

Minimum number of digits.

-> IO Int

Number of bytes written.

Store an ASCII Int into a buffer, producing the number of bytes written.

storeIntPad#

Arguments

:: Addr#

Address of output buffer.

-> Int#

Int to store.

-> Int#

Minimum number of digits.

-> IO Int

Number of bytes written.

Store an ASCII Int into a buffer, producing the number of bytes written.

• This function is set to NOINLINE, so it can be safely called from multiple places in the program.

storeIntPadWith#

Arguments

:: (Int# -> IO buf)

Function to allocate a new output buffer, given the length in bytes.

-> (buf -> Int# -> Int# -> IO ())

Function to write a byte to the buffer, given the index and byte value.

-> Int#

Int to store.

-> Int#

Pad out result to achieve at this many digits.

-> (buf -> Int# -> IO b)

Continuation for buffer and bytes written.

-> IO b

Like storeIntWith#, but add leading zeros to the front of the integer to pad it out to at least the given number of digits.