[Haskell-beginners] definition of combinator
jakubuv at gmail.com
Mon Aug 24 06:23:29 EDT 2009
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
> 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,
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.
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