Unsafe functions
From HaskellWiki
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Unsafe functions can break type safety (unsafeCoerce#, unsafePerformIO), | Unsafe functions can break type safety (unsafeCoerce#, unsafePerformIO), | ||
| - | interfere with lazy IO (unsafeInterleaveIO), or break | + | interfere with lazy IO (unsafeInterleaveIO), or break [http://en.wikipedia.org/wiki/Parametricity parametricity] (seq). |
Their use (except in the case of <hask>seq</hask>) would require some | Their use (except in the case of <hask>seq</hask>) would require some | ||
kind of assurance on the part of the programmer that what they're doing | kind of assurance on the part of the programmer that what they're doing | ||
is safe. | is safe. | ||
| + | |||
| + | "unsafe" is also a keyword which can be used in a [http://haskell.org/haskellwiki/Performance/FFI foreign import declaration]. | ||
{{stub}} | {{stub}} | ||
[[Category:Idioms]] | [[Category:Idioms]] | ||
Current revision
There are a number of unsafe functions in the libraries.
- unsafePerformIO :: IO a -> a
- unsafeInterleaveIO :: IO a -> IO a
- unsafeInterleaveST :: ST s a -> ST s a
- unsafeIOToST :: IO a -> ST s a
- unsafeIOToSTM :: IO a -> STM a
- unsafeFreeze, unsafeThaw
- unsafeCoerce# :: a -> b
- seq :: a -> b -> b
Unsafe functions can break type safety (unsafeCoerce#, unsafePerformIO), interfere with lazy IO (unsafeInterleaveIO), or break parametricity (seq).
Their use (except in the case ofseq
kind of assurance on the part of the programmer that what they're doing is safe.
"unsafe" is also a keyword which can be used in a foreign import declaration.
This article is a stub. You can help by expanding it.
