racket/collects/lang/private/intermediate-funs.rkt
2010-04-27 16:50:15 -06:00

63 lines
3.1 KiB
Racket

(module intermediate-funs scheme/base
(require "teachprims.ss" "and-or-map.ss"
mzlib/etc
scheme/list
syntax/docprovide
(for-syntax scheme/base))
(provide-and-document
procedures
(all-from-except beginner: lang/private/beginner-funs procedures
+ * - / append)
("Numbers (relaxed conditions)"
(+ (number ... -> number) "to add all given numbers")
(* (number ... -> number) "to multiply all given numbers")
(- (number ... -> number) "to subtract from the first all remaining numbers")
(/ (number ... -> number) "to divide the first by all remaining numbers")
)
("Lists"
((intermediate-append append) ((listof any) ... -> (listof any))
"to create a single list from several, by juxtaposition of the items"))
("Higher-Order Functions"
(map ((X ... -> Z) (listof X) ... -> (listof Z))
"to construct a new list by applying a function to each item on one or more existing lists")
(for-each ((any ... -> any) (listof any) ... -> void)
"to apply a function to each item on one or more lists for effect only")
(filter ((X -> boolean) (listof X) -> (listof X))
"to construct a list from all those items on a list for which the predicate holds")
((intermediate-foldr foldr) ((X Y -> Y) Y (listof X) -> Y)
"(foldr f base (list x-1 ... x-n)) = (f x-1 ... (f x-n base))")
((intermediate-foldl foldl) ((X Y -> Y) Y (listof X) -> Y)
"(foldl f base (list x-1 ... x-n)) = (f x-n ... (f x-1 base))")
(build-list (nat (nat -> X) -> (listof X))
"(build-list n f) = (list (f 0) ... (f (- n 1)))")
((intermediate-build-string build-string) (nat (nat -> char) -> string)
"(build-string n f) = (string (f 0) ... (f (- n 1)))")
((intermediate-quicksort quicksort) ((listof X) (X X -> boolean) -> (listof X))
"to construct a list from all items on a list in an order according to a predicate")
((intermediate-sort sort) ((listof X) (X X -> boolean) -> (listof X))
"to construct a list from all items on a list in an order according to a predicate")
((intermediate-andmap andmap) ((X -> boolean) (listof X) -> boolean)
"(andmap p (list x-1 ... x-n)) = (and (p x-1) ... (p x-n))")
((intermediate-ormap ormap) ((X -> boolean) (listof X) -> boolean)
"(ormap p (list x-1 ... x-n)) = (or (p x-1) ... (p x-n))")
(argmin ((X -> real) (listof X) -> X)
"to find the (first) element of the list that minimizes the output of the function")
(argmax ((X -> real) (listof X) -> X)
"to find the (first) element of the list that maximizes the output of the function")
(memf ((X -> boolean) (listof X) -> (union false (listof X)))
"to determine whether the first argument produces true for some value in the second argument")
(apply ((X-1 ... X-N -> Y) X-1 ... X-i (list X-i+1 ... X-N) -> Y)
"to apply a function using items from a list as the arguments")
(compose ((Y-1 -> Z) ... (Y-N -> Y-N-1) (X-1 ... X-N -> Y-N) -> (X-1 ... X-N -> Z))
"to compose a sequence of procedures into a single procedure")
(procedure? (any -> boolean)
"to determine if a value is a procedure"))))