Trains have been discussed recently in another thread. It is useful to review some of the material on the topic.
http://keiapl.org/rhui/remember.htm#fork0 Quote: For years, Ken had struggled to find a way to write f+g as in calculus, from the "scalar operators" in Operators and Functions [5, section 4], through the "til" operator in Practical Uses of a Model of APL [6] and Rationalized APL [7, p. 18], and finally forks. Forks are defined as follows: (f g h) y <-> (f y) g (h y) x (f g h) y <-> (x f y) g (x h y) Moreover, (f g p q r) <-> (f g (p q r)) . Thus to write f+g as in calculus, one writes f+g in J. http://www.jsoftware.com/papers/fork.htm The hook and fork paper from 1988 http://portal.acm.org/citation.cfm?id=114055.114077 Tacit Definition paper from 1991. Presents proof of expressive completeness and a translator from explicit to tacit. http://www.jsoftware.com/jwiki/Essays/Capped_Fork Regarding [: g h http://keiapl.org/anec/#nvv Regarding noun-verb-verb http://www.jsoftware.com/jwiki/Essays/Hook_Conjunction%3F Alternatives for hook ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
