Unicode.Internal.Bits

Fast, static bitmap lookup utilities

Documentation

lookupBit64 :: Addr# -> Int -> Bool

lookup64 addr index looks up the bit stored at bit index index using a bitmap starting at the address addr. Looks up the 64-bit word containing the bit and then the bit in that word. The caller must make sure that the 64-bit word at the byte address (addr + index / 64) * 8 is legally accessible memory.

lookupIntN

Arguments

:: Addr#

Bitmap address

-> Int

Word index

-> Int

Resulting word as Int

lookupIntN addr index looks up for the index-th 8-bits word in the bitmap starting at addr, then convert it to an Int.

The caller must make sure that:

• ceiling (addr + (n * 8)) is legally accessible Word8.

Since: 0.3.0