You cannot select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
32 lines
1.1 KiB
Racket
32 lines
1.1 KiB
Racket
#lang scribble/manual
|
|
|
|
@(require scribble/eval (for-label racket sugar))
|
|
|
|
@(define my-eval (make-base-eval))
|
|
@(my-eval `(require sugar))
|
|
|
|
@title{Cache}
|
|
@defmodule[sugar/cache]
|
|
|
|
If, like Ricky Bobby and me, you want to go fast, then try using more caches. They're wicked fast.
|
|
|
|
@defproc[
|
|
(make-caching-proc
|
|
[proc procedure?])
|
|
procedure?]
|
|
Make a caching version of @racket[_proc]. This means a hash table will be attached to @racket[_proc], and result values will automatically be saved & retrieved. The arguments to the procedure are used as the hash key.
|
|
|
|
In the example below, notice that both invocations of @racketfont{slow-op} take approximately the same time, whereas the second invocation of @racketfont{fast-op} uses the cache instead and thus is nearly instantaneous.
|
|
|
|
@examples[#:eval my-eval
|
|
(define (slow-op x) (for/sum ([i (in-range 100000000)]) i))
|
|
(time (slow-op 42))
|
|
(time (slow-op 42))
|
|
(define fast-op (make-caching-proc slow-op))
|
|
(time (fast-op 42))
|
|
(time (fast-op 42))
|
|
]
|
|
|
|
@defform[(define/caching (name arg ... . rest-arg) body ...)]
|
|
Like @racket[define], but automatically uses @racket[make-caching-proc] to define a caching version of the function.
|