In Computer Programming
Many programming languages, such as Python, allow the direct expression of lists of numbers, and even functions that allow an arbitrary number of parameters. If such a language has a function that returns the product of all the numbers in a list, it usually works like this:
listprod( ) --> 30 listprod( ) --> 6 listprod( ) --> 2 listprod( ) --> 1This convention sometimes helps avoid having to code special cases like "if length of list is 1" or "if length of list is zero" as special cases.
Many programming languages do not permit the direct expression of the empty product, because they do not allow expressing lists. Multiplication is taken to be an infix operator and therefore a binary operator. Languages implementing variadic functions are the exception. For example, the fully parenthesized prefix notation of Lisp languages gives rise to a natural notation for nullary functions:
(* 2 2 2) ; evaluates to 8 (* 2 2) ; evaluates to 4 (* 2) ; evaluates to 2 (*) ; evaluates to 1Read more about this topic: Empty Product
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