view 5-Erlang/day1.erl @ 103:98be775c533c default tip

An odd "non-determinism" example from StackOverflow It is clever, but doesn't make much sense as to how it gets its results
author IBBoard <dev@ibboard.co.uk>
date Sun, 14 Jul 2019 13:44:13 +0100
parents 32f018861e36
children
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-module(day1).
-export([wordcount/1]).
-export([count_to_ten/0]).
-export([success_or_error/1]).

wordcount("") -> 0;
wordcount([_|[]]) -> 1;
% NOTE: We can't use " " here - because it is a string and hence an array, not a character.
% Instead we get a slightly ugly "dollar space"
% Note the funky extra match to handle multiple consecutive spaces (although we still don't handle leading or trailing spaces)
wordcount([$ |[$ |Tail]]) -> wordcount([$ |Tail]);
wordcount([$ |Tail]) -> 1 + wordcount(Tail);
wordcount([_|Tail]) -> wordcount(Tail).

count_to(1) -> io:fwrite("~B ", [1]);
count_to(N) -> count_to(N-1), io:fwrite("~B ", [N]).

count_to_ten() -> count_to(10), io:fwrite("~n").

success_or_error({error, Message}) -> io:fwrite("error: ~s~n", [Message]);
success_or_error(success) -> io:fwrite("success~n").