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## FloatingHex: Read/Write Hexadecimal floats
[](http://hackage.haskell.org/package/FloatingHex)
[](http://travis-ci.org/LeventErkok/FloatingHex)
### Hexadecimal Floats
For syntax reference, 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. Some examples are:
```
[hf|0x1p+1|]
[hf|0x1p+8|]
[hf|0x1.b7p-1|]
[hf|0x1.fffffffffffffp+1023|]
[hf|0X1.921FB4D12D84AP-1|]
```
This format allows for concise and precise string representation for floating point numbers. Note that you need the `QuasiQuotes` extension of GHC to be able to write these literals.
## Example
```haskell
{-# LANGUAGE QuasiQuotes #-}
import Data.Numbers.FloatingHex
-- expressions
f :: Double
f = [hf|0x1.f44abd5aa7ca4p+25|]
-- patterns
g :: Float -> String
g [hf|0x1p1|] = "two!"
g [hf|0x1p-1|] = "half!"
g d = "something else: " ++ show d
-- showing hexadecimal floats
test = showHFloat [hf|0x1.f44abd5aa7ca4p+25|] ""
```
(Note that while the quasiquoter allows for floating-point patterns, it is usually not a good idea to use floating-point literals in pattern matching.)
### Thanks
The following people reported bugs, provided comments/feedback, or contributed to the development of
FloatingHex in various ways: Herbert Valerio Riedel.
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