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.
102 lines
4.1 KiB
Racket
102 lines
4.1 KiB
Racket
#lang racket/base
|
|
(require racket/contract racket/list racket/string racket/match)
|
|
(require (only-in racket/format ~a))
|
|
(require (only-in racket/bool nor))
|
|
(require (only-in xml xexpr/c))
|
|
(module+ test (require rackunit))
|
|
|
|
(require "tools.rkt")
|
|
(provide (all-defined-out))
|
|
|
|
|
|
;; Find adjacent newline characters in a list and merge them into one item
|
|
;; Scribble, by default, makes each newline a separate list item
|
|
;; In practice, this is worthless.
|
|
(define/contract (merge-newlines x)
|
|
(list? . -> . list?)
|
|
(define (newline? x)
|
|
(and (string? x) (equal? "\n" x)))
|
|
(define (not-newline? x)
|
|
(not (newline? x)))
|
|
|
|
(define (really-merge-newlines xs [acc '()])
|
|
(if (empty? xs)
|
|
acc
|
|
;; Try to peel the newlines off the front.
|
|
(let-values ([(leading-newlines remainder) (splitf-at xs newline?)])
|
|
(if (not (empty? leading-newlines)) ; if you got newlines ...
|
|
;; combine them into a string and append them to the accumulator,
|
|
;; and recurse on the rest
|
|
(really-merge-newlines remainder (append acc (list (string-join leading-newlines ""))))
|
|
;; otherwise peel off elements up to the next newline, append them to accumulator,
|
|
;; and recurse on the rest
|
|
(really-merge-newlines (dropf remainder not-newline?)
|
|
(append acc (takef remainder not-newline?)))))))
|
|
|
|
(cond
|
|
[(list? x) (really-merge-newlines (map merge-newlines x))]
|
|
[else x]))
|
|
|
|
(module+ test
|
|
(check-equal? (merge-newlines '(p "\n" "foo" "\n" "\n" "bar" (em "\n" "\n" "\n")))
|
|
'(p "\n" "foo" "\n\n" "bar" (em "\n\n\n"))))
|
|
|
|
|
|
|
|
;; todo: add native support for list-xexpr
|
|
;; decode triple newlines to list items
|
|
|
|
|
|
;; convert numbers to strings
|
|
;; maybe this isn't necessary
|
|
(define (stringify x)
|
|
(map-tree (λ(i) (if (number? i) (->string i) i)) x))
|
|
|
|
(module+ test
|
|
(check-equal? (stringify '(p 1 2 "foo" (em 4 "bar"))) '(p "1" "2" "foo" (em "4" "bar"))))
|
|
|
|
|
|
|
|
;; decoder wireframe
|
|
(define/contract (decode nx
|
|
#:exclude-xexpr-tags [excluded-xexpr-tags '()]
|
|
#:xexpr-tag-proc [xexpr-tag-proc (λ(x)x)]
|
|
#:xexpr-attr-proc [xexpr-attr-proc (λ(x)x)]
|
|
#:xexpr-elements-proc [xexpr-elements-proc (λ(x)x)]
|
|
#:block-xexpr-proc [block-xexpr-proc (λ(x)x)]
|
|
#:inline-xexpr-proc [inline-xexpr-proc (λ(x)x)]
|
|
#:string-proc [string-proc (λ(x)x)])
|
|
;; use xexpr/c for contract because it gives better error messages
|
|
((xexpr/c) (#:exclude-xexpr-tags list?
|
|
#:xexpr-tag-proc procedure?
|
|
#:xexpr-attr-proc procedure?
|
|
#:xexpr-elements-proc procedure?
|
|
#:block-xexpr-proc procedure?
|
|
#:inline-xexpr-proc procedure?
|
|
#:string-proc procedure?)
|
|
. ->* . tagged-xexpr?)
|
|
(when (not (tagged-xexpr? nx))
|
|
(error (format "decode: ~v not a full tagged-xexpr" nx)))
|
|
|
|
|
|
(define (&decode x)
|
|
(cond
|
|
[(tagged-xexpr? x) (let-values([(tag attr elements) (break-tagged-xexpr x)])
|
|
(if (tag . in? . excluded-xexpr-tags)
|
|
x ; let x pass through untouched
|
|
(let ([decoded-xexpr (apply make-tagged-xexpr
|
|
(map &decode (list tag attr elements)))])
|
|
((if (block-xexpr? decoded-xexpr)
|
|
block-xexpr-proc
|
|
inline-xexpr-proc) decoded-xexpr))))]
|
|
[(xexpr-tag? x) (xexpr-tag-proc x)]
|
|
[(xexpr-attr? x) (xexpr-attr-proc x)]
|
|
;; need this for operations that may depend on context in list
|
|
[(xexpr-elements? x) (map &decode (xexpr-elements-proc x))]
|
|
[(string? x) (string-proc x)]
|
|
;; if something has made it through undecoded, that's a problem
|
|
[else (error "Can't decode" x)]))
|
|
|
|
|
|
(&decode nx))
|