On Monday, February 2, 2015 at 1:13:30 PM UTC+5:30, Paul Rubin wrote: > Steven D'Aprano writes: > > No apples and no oranges aren't the same thing, but if somebody is > > expecting > > no apples, and I give them no oranges instead, it would be churlish for > > them > > to complain that none of them are the wrong kind of fruit. > > https://davedevine.wordpress.com/2011/01/20/the-sartre-joke/
Actually the Sartre joke is more applicable to haskell than it might appear at first blush. li = [1,2,3] : [Int] -- a monomorphic type just as lc = ['a','b','c'] : [Char] lli = [[1,2],[3]] : [[Int]] However [] is a polymorphic value ie [] : [t] -- t is a type variable And now if we take tail (tail (tail li)) you get [] just as if you take tail (tail lli) However the two '[]-s' are of different types and so if you try to say append them you will get a Sartre error: The list of no integers is incompatible with the list of no lists of integers -- https://mail.python.org/mailman/listinfo/python-list
