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Update readme to reflect recent changes.wq

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Linus 2020-11-09 13:35:43 +01:00
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README.md
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@ -5,10 +5,10 @@ WARNING: CURRENTLY PRE-ALPHA. The examples in this document are not consistent w
goof-loops aims to be an amalgamation of the racket for loops and Alex Shinn's (chibi-loop). We are many that found racket's for loops a breeze of fresh air, but in the end their most general forms (for/fold and for/foldr) are kinda odd to work with. If you choose not to use those general for loops, you cannot express arbitrary transformations, like say a fibonacci sequence, since for clauses cannot reference eachother. goof-loop tries to fix this: goof-loops aims to be an amalgamation of the racket for loops and Alex Shinn's (chibi-loop). We are many that found racket's for loops a breeze of fresh air, but in the end their most general forms (for/fold and for/foldr) are kinda odd to work with. If you choose not to use those general for loops, you cannot express arbitrary transformations, like say a fibonacci sequence, since for clauses cannot reference eachother. goof-loop tries to fix this:
``` ```
(loop ((:for a (in 0 b)) (loop ((a (in 0 b))
(:for b (in 1 (+ a b))) (b (in 1 (+ a b)))
(:for count (up-from 0 (to 1000))) (count (up-from 0 (to 1000)))
(:acc acc (listing b))) (acc (listing b)))
=> acc => acc
(display b) (newline)) (display b) (newline))
``` ```
@ -18,11 +18,11 @@ The above example will display and accumulate the 1000 first fibonacci numbers.
Compared to foof-loop, some things are added. Apart from minor syntactic changes, subloops are supported. The best way is to show: Compared to foof-loop, some things are added. Apart from minor syntactic changes, subloops are supported. The best way is to show:
``` ```
(define lst '((1 2) 'dud (3 4) (5 6))) (define lst '((1 2) dud (3 4) (5 6)))
(loop ((:for a (in-list lst)) (loop ((a (in-list lst))
(:when (pair? a)) :when (pair? a)
(:for b (in-list a)) (b (in-list a))
(:acc acc (summing b))) (acc (summing b)))
=> acc) => acc)
``` ```
@ -31,11 +31,11 @@ This will sum all the sublists of lst and produce the result 21. Any :when, :unl
Accumulators can be in any of the loop's stages: Accumulators can be in any of the loop's stages:
``` ```
(loop ((:for a (in-list '(1 2 3))) (loop ((a (in-list '(1 2 3)))
(:acc aa (summing a)) (aa (summing a))
:subloop :subloop
(:for b (up-from a (to (+ a 2)))) (b (up-from a (to (+ a 2))))
(:acc ab (listing b))) (ab (listing b)))
=> (values aa ab)) => (values aa ab))
;; => (values 6 (1 2 2 3 3 4)) ;; => (values 6 (1 2 2 3 3 4))
``` ```
@ -73,7 +73,7 @@ Due to clause reordering, positional updates are not supported. If you want to u
You can of course still have a larger control of your loops: You can of course still have a larger control of your loops:
``` ```
(loop loopy-loop ((:for a (up-from 1 (to 11)))) (loop loopy-loop ((a (up-from 1 (to 11))))
=> '() => '()
(if (odd? a) (if (odd? a)
(cons (* a (- a)) (loopy-loop)) (cons (* a (- a)) (loopy-loop))
@ -87,9 +87,9 @@ Named updates also work.
``` ```
;; Shamelessly stolen from Taylor Campbell's foof-loop documentation ;; Shamelessly stolen from Taylor Campbell's foof-loop documentation
(define (partition list predicate) (define (partition list predicate)
(loop continue ((:for element (in-list list)) (loop continue ((element (in-list list))
(:acc satisfied (in '())) (satisfied (folding '()))
(:acc unsatisfied (in '()))) (unsatisfied (folding '())))
=> (values (reverse satisfied) => (values (reverse satisfied)
(reverse unsatisfied)) (reverse unsatisfied))
(if (predicate element) (if (predicate element)