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.
49 lines
1.4 KiB
Racket
49 lines
1.4 KiB
Racket
#lang racket/base
|
|
(require (for-syntax racket/base syntax/parse))
|
|
|
|
(provide #%module-begin
|
|
;; We reuse Racket's treatment of raw datums, specifically
|
|
;; for strings and numbers:
|
|
#%datum
|
|
|
|
;; And otherwise, we provide definitions of these three forms.
|
|
;; During compiliation, Racket uses these definitions to
|
|
;; rewrite into for loops, displays, and newlines.
|
|
drawing rows chunk)
|
|
|
|
;; Define a few compile-time functions to do the syntax rewriting:
|
|
(begin-for-syntax
|
|
(define (compile-drawing drawing-stx)
|
|
(syntax-parse drawing-stx
|
|
[({~literal drawing} row-stxs ...)
|
|
|
|
(syntax/loc drawing-stx
|
|
(begin row-stxs ...))]))
|
|
|
|
(define (compile-rows row-stx)
|
|
(syntax-parse row-stx
|
|
[({~literal rows}
|
|
({~literal repeat} repeat-number)
|
|
chunks ...
|
|
";")
|
|
|
|
(syntax/loc row-stx
|
|
(for ([i repeat-number])
|
|
chunks ...
|
|
(newline)))]))
|
|
|
|
(define (compile-chunk chunk-stx)
|
|
(syntax-parse chunk-stx
|
|
[({~literal chunk} chunk-size chunk-string)
|
|
|
|
(syntax/loc chunk-stx
|
|
(for ([k chunk-size])
|
|
(display chunk-string)))])))
|
|
|
|
|
|
;; Wire up the use of "drawing", "rows", and "chunk" to these
|
|
;; transformers:
|
|
(define-syntax drawing compile-drawing)
|
|
(define-syntax rows compile-rows)
|
|
(define-syntax chunk compile-chunk)
|