Bjorn Buckwalter wrote:
Dear all,
Does it make good sense that 'and []' returns 'True' and 'or []'
returns 'False'?
It's certainly what I would expect it to do, based on several ways of
thinking.
1: If we define the function using explicit recursion:
and (x:xs) = x && and xs
Therefore and [] has to be True. Similar logic for or.
2: My instinct is to consider "and = all (== True)", while "or = any (==
True)". It's even clearer to me that "all [] = True" and "any [] =
False" (similiar to Miguel's post).
Thanks,
Neil.
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