61 lines
1.5 KiB
Racket
61 lines
1.5 KiB
Racket
#lang racket/base
|
|
|
|
(provide record-implementations!
|
|
record-exports!
|
|
lookup-implementations
|
|
lookup-exports)
|
|
|
|
(define-struct record (path impls))
|
|
(define-struct export (path exports))
|
|
|
|
(define records '())
|
|
(define exports '())
|
|
|
|
;; record!: path (listof string) -> void
|
|
(define (record-implementations! a-path impls)
|
|
(set! records (cons (make-record a-path impls)
|
|
records)))
|
|
|
|
|
|
;; record-exports!: path (listof symbol) -> void
|
|
(define (record-exports! a-path export-names)
|
|
(set! exports (cons (make-export a-path export-names)
|
|
exports)))
|
|
|
|
|
|
(define (my-foldl f acc lst)
|
|
(cond
|
|
[(null? lst)
|
|
acc]
|
|
[else
|
|
(my-foldl f (f (car lst) acc) (cdr lst))]))
|
|
|
|
|
|
(define (my-filter f lst)
|
|
(cond
|
|
[(null? lst)
|
|
'()]
|
|
[(f (car lst))
|
|
(cons (car lst) (my-filter f (cdr lst)))]
|
|
[else
|
|
(my-filter f (cdr lst))]))
|
|
|
|
|
|
;; lookup-implementations: path -> (listof string)
|
|
(define (lookup-implementations a-path)
|
|
(my-foldl (lambda (a-record perms)
|
|
(append (record-impls a-record) perms))
|
|
'()
|
|
(my-filter (lambda (a-record)
|
|
(equal? a-path (record-path a-record)))
|
|
records)))
|
|
|
|
|
|
;; lookup-exports: path -> (listof symbol)
|
|
(define (lookup-exports a-path)
|
|
(my-foldl (lambda (an-export exports)
|
|
(append (export-exports an-export) exports))
|
|
'()
|
|
(my-filter (lambda (an-export)
|
|
(equal? a-path (export-path an-export)))
|
|
exports))) |