Copyright | (c) Levent Erkok |
---|---|

License | BSD3 |

Maintainer | erkokl@gmail.com |

Stability | experimental |

Safe Haskell | None |

Language | Haskell2010 |

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.

- hf :: QuasiQuoter
- class RealFloat a => FloatingHexReader a where
- showHFloat :: RealFloat a => a -> ShowS

## QuasiQuoting

hf :: QuasiQuoter Source #

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`

## Reading hex-floats

class RealFloat a => FloatingHexReader a where Source #

Due to intricacies of conversion between
`Float`

and `Double`

types (see http://ghc.haskell.org/trac/ghc/ticket/3676), we explicitly introduce
a class to do the reading properly.

readHFloat :: String -> Maybe a Source #

Convert a hex-float from a string, if possible.

FloatingHexReader Double Source # | The Double instance |

FloatingHexReader Float Source # | The Float instance |

## Showing hex-floats

showHFloat :: RealFloat a => a -> ShowS Source #

Show a floating-point value in the hexadecimal format, similar to the `%a`

specifier in C's printf.

`>>>`

"0x1.a86b851eb851fp7"`showHFloat (212.21 :: Double) ""`

`>>>`

"-0x1.9851ecp3"`showHFloat (-12.76 :: Float) ""`

`>>>`

"-0x0p+0"`showHFloat (-0 :: Double) ""`