[Haskell-cafe] How to understand `|` in this code snippet ?
lee.duhem at gmail.com
Sat Feb 27 04:26:59 EST 2010
On Sat, Feb 27, 2010 at 5:07 PM, zaxis <z_axis at 163.com> wrote:
> xxxMain = do
> timeout <- getEnv "xxx_TIMEOUT"
> case timeout of
> Just str | [(t, _)] <- reads str -> do
> addTimeout t (hPutStrLn stderr "*** TIMEOUT" >> _exit 1)
> return ()
> _ -> return ()
> What does the `|` mean in "Just str | [(t, _)] <- reads str" ?
> Is it a logical `or` ?
It's part of a case expression, see
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