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[](http://hackage.haskell.org/package/silently)
[](https://stackage.org/nightly/package/silently)
[](https://www.stackage.org/package/silently)
[](https://github.com/hspec/silently/actions)
# silently
Silently is a package that allows you to run an `IO` action and
prevent it from writing to `stdout`, or any other handle, by using
`silence`. Or you can capture the output for yourself using `capture`.
For example, the program
```haskell
import System.IO.Silently
main = do
putStr "putStrLn: " >> putStrLn "puppies!"
putStr "silenced: " >> silence (putStrLn "kittens!")
putStrLn ""
(captured, result) <- capture (putStr "wookies!" >> return 123)
putStr "captured: " >> putStrLn captured
putStr "returned: " >> putStrLn (show result)
```
will print:
```
putStrLn: puppies!
silenced:
captured: wookies!
returned: 123
```
## Limitations
Capturing/silencing might not work as expected if the action uses the FFI
or conceals output under `unsafePerformIO` or similar unsafe operations.
Examples:
- FFI: https://github.com/hspec/silently/issues/3
- `unsafePerformIO`: https://github.com/bos/filemanip/issues/22
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