Fri Nov 19 1999, Greg O'Keefe ->
> The Haskell 98 Report contains the following example, in section 7.2 on
> page 89:
>
> main = readFile "input-file" >>= \ s ->
> writeFile "output-file" (filter isAscii s) >>
> putStr "Filtering succesful\n"
>
> I am just learning Haskell, and this seemed extremely mysterious to me
> until I realised that the \ s -> on the first line and the stuff before
> the >> on the second line go together to make an expression of type
> String -> IO String. In other words, it makes much more sense to me
> when written as:
>
> main = readFile "input-file" >>=
> \ s -> writeFile "output-file" (filter isAscii s) >>
> putStr "Filtering succesful\n"
>
> My question is: is there some good reason why it is set out the way it
> is in the report?
The style in the Haskell report (and the design of the >>= operator) is
meant to symbolize that the value bound to s comes from the first
expression.
n.
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