The statement x = a # b # c abbreviates x = '#'(a b c), which constructs a tuple with label '#' and fields a, b and c. for example, the following two calls do the same thing: {browse '#'(a b c)} {browse a#b#c} pairs are often used as elements of lists. these lists are called pairlists (also called lists of pairs). for example, the following list is a pairlist: [a#1 b#2 c#3]. but both pairs and cons are constructed with infix operators ('#' and '|'). give examples which show that '#' has a higher precedence (binds tighter) than '|'.