On 11 May 2008, at 00:36, PR Stanley wrote:
Hi folks
data Maybe a = Nothing | Just a
What is the underlying rationale for the Maybe data type? is it the
safe style of programming it encourages/
Something tells me this is going to start a lengthy discussion. :-)
Pure and simple -- it allows you to represent partial functions.
Looking up a map will only sometimes find a value, so we either return
Nothing, or Just that value.
Bob
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