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.
beautiful-racket/beautiful-racket/br/demo/jsonic-2/indenter.rkt

46 lines
1.2 KiB
Racket

#lang br
(require br/indent racket/gui/base)
(provide indent-jsonic)
(define indent-width 2)
(define (left-bracket? c) (member c '(#\{ #\[)))
(define (right-bracket? c) (member c '(#\} #\])))
;; if this line begins with } or ], outdent.
;; if last line begins with { or [, indent.
;; otherwise use previous indent
(define/contract (indent-jsonic textbox [tbpos 0])
((is-a?/c text%) exact-nonnegative-integer? . -> .
(or/c exact-nonnegative-integer? #f))
(define this-line (line textbox tbpos))
(define prev-line (previous-line textbox tbpos))
(define prev-indent (or (line-indent textbox prev-line) 0))
(define this-indent
(cond
[(left-bracket? (char textbox (line-start-visible textbox prev-line)))
(+ prev-indent indent-width)]
[(right-bracket? (char textbox (line-start-visible textbox this-line)))
(- prev-indent indent-width)]
[else prev-indent]))
(and (exact-positive-integer? this-indent) this-indent))
(module+ test
(require rackunit)
(define test-str #<<here
#lang br/demo/jsonic
{
"value",
"string":
[
{
"array": @$(range 5)$@,
"object": @$(hash 'k1 "valstring")$@
}
]
// "bar"
}
here
)
(display (apply-indenter indent-jsonic test-str)))