/*
 * loop.h
 *
 * Iteration functions. This has *a lot* of similarity to try/catch -- 
 * essentially what `recur` does is throw a special purpose exception which is
 * caught by `loop`.
 *
 * (c) 2021 Simon Brooke <simon@journeyman.cc>
 * Licensed under GPL version 2.0, or, at your option, any later version.
 */