fib 0 = 1 fib 1 = 1 fib n | n >= 2 = fib (n-1) + fib (n-2)
def fib(0), do: 1 def fib(1), do: 1 def fib(n) when n >= 2, do: fib(n-1) + fib(n-2)
match [head] + tail in [0, 1, 2, 3]: print(head, tail)
match x with | Some x => println$ x; | None => println "NONE"; endmatch;
Languages without Pattern Matching include progsbase
In computer science, pattern matching is the act of checking a given sequence of tokens for the presence of the constituents of some pattern. In contrast to pattern recognition, the match usually has to be exact: "either it will or will not be a match." The patterns generally have the form of either sequences or tree structures. Uses of pattern matching include outputting the locations (if any) of a pattern within a token sequence, to output some component of the matched pattern, and to substitute the matching pattern with some other token sequence (i.e., search and replace). Read more on Wikipedia...