Paul: 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. :-)
Bob: 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.
Paul: Would yu like to demonstrate this in an example?
Cheers, Paul
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