Difference between revisions of "Unsafe functions"

Revision as of 05:30, 11 August 2022

I think unsafePerformIO might actually be a pretty good alternative, we just need to understand how to use it safely [...]

Victor Miraldo.

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 of seq) would require some 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.

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 I think <code>unsafePerformIO</code> might actually be a pretty good alternative, we just need to understand how to use it safely [...]
 <tt>[https://discourse.haskell.org/t/using-unsafeperformio-safely/4146/49 Victor Miraldo.]</tt>
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 is safe.
-"unsafe" is also a keyword which can be used in a [http://haskell.org/haskellwiki/Performance/FFI foreign import declaration].
+<code>unsafe</code> is also a keyword which can be used in a [http://haskell.org/haskellwiki/Performance/FFI foreign import declaration].
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Difference between revisions of "Unsafe functions"

Revision as of 05:30, 11 August 2022

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