Hi Michael, On Sun, Aug 23, 2009 at 05:44:27PM -0700, Michael Mossey wrote:
"A combinator is a higher-order function that uses only function application and earlier defined combinators to define a result from its arguments."
Okay, so I believe a "higher-order function" is a function that takes function(s) as its argument(s). I don't know what "uses only function application" means. Application of what functions to what?
Briefly, a combinator applies “earlier defined combinators” to “its arguments”. But remember that a combinator's argument can be a function as well, so it may become more complicated. Then it simply applies functions (other combinators, combinator's arguments, library functions) to their arguments (other combinators, combinator's arguments, library functions, constants, ...). Finally, I guess that the word “only” suggests that it doesn't read any parsed text by itself but it only calls (combine) other parsers. Sincerely, Jan. -- Heriot-Watt University is a Scottish charity registered under charity number SC000278.