Data.Numbers.FloatingHex

Reading/Writing hexadecimal floating-point numbers.

See: http://www.open-std.org/jtc1/sc22/wg14/www/docs/n1256.pdf, pages 57-58. We slightly diverge from the standard and do not allow for the "floating-suffix," as the type inference of Haskell makes this unnecessary.

Documentation

hf :: QuasiQuoter

A quasiquoter for hexadecimal floating-point literals. See: http://www.open-std.org/jtc1/sc22/wg14/www/docs/n1256.pdf, pages 57-58. We slightly diverge from the standard and do not allow for the "floating-suffix," as the type inference of Haskell makes this unnecessary.

Example:

{-# LANGUAGE QuasiQuotes #-}
import Data.Numbers.FloatingHex

f :: Double
f = [hf|0x1.f44abd5aa7ca4p+25|]

With these definitions, f will be equal to the number 6.5574266708245546e7

showHFloat :: RealFloat a => a -> ShowS

Show a floating-point value in the hexadecimal format.

NB. While this function will print a faithful (i.e., correct) value, it is not 100% compatible with the %a modifier as found in the C's printf implementation.

>>> showHFloat (212.21 :: Double) ""
"0x1.a86b851eb851fp7"
>>> showHFloat (-12.76 :: Float) ""
"-0xc.c28f6p0"