pull/10/head
Matthew Butterick 8 years ago
parent acf9e65315
commit f49f42003a

@ -1,22 +1,30 @@
#lang br
(require "lexer.rkt" brag/support)
(provide color-basic)
(provide basic-colorer)
(define (color-basic port)
(define srcloc-tok (basic-lexer port))
(match srcloc-tok
[(? eof-object?) (values srcloc-tok 'eof #f #f #f)]
[else ; reverse-engineer with `match-define`
(define (basic-colorer port)
(define next-char (peek-char port))
(define (handle-read-error exn)
(define exn-srclocs (exn:fail:read-srclocs exn))
(srcloc-token (token 'ERROR (string next-char)) (car exn-srclocs)))
(define srcloc-tok (with-handlers ([exn:fail:read? handle-read-error])
(basic-lexer port)))
(cond
[(eof-object? srcloc-tok) (values srcloc-tok 'eof #f #f #f)]
[else
(match-define (srcloc-token (token-struct type val _ _ _ _ _)
(srcloc _ _ _ pos span)) srcloc-tok)
(define (color cat [paren #f])
(values (or val "") cat paren pos (+ pos span)))
(match type
['STRING (color 'string)]
['REM (color 'comment)]
[else (match val
[(? number?) (color 'constant)]
[(? symbol?) (color 'symbol)]
["(" (color 'parenthesis '|(|)]
[")" (color 'parenthesis '|)|)]
[else (color 'no-color)])])]))
(match-define (list cat paren)
(match type
['STRING '(string #f)]
['REM '(comment #f)]
['ERROR '(error #f)]
[else (match val
[(? number?)'(constant #f)]
[(? symbol?) '(symbol #f)]
["(" '(parenthesis |(|)]
[")" '(parenthesis |)|)]
[else '(no-color #f)])]))
(values (or val "") cat paren pos (+ pos span))]))
(apply-colorer basic-colorer "foo")

@ -1,3 +1,3 @@
#lang br
(require "line.rkt" "go.rkt" "if.rkt" "expr.rkt" "for.rkt" "misc.rkt")
(provide (all-from-out "line.rkt" "go.rkt" "if.rkt" "expr.rkt" "for.rkt" "misc.rkt"))
(require "line.rkt" "go.rkt" "if.rkt" "expr.rkt" "misc.rkt")
(provide (all-from-out "line.rkt" "go.rkt" "if.rkt" "expr.rkt" "misc.rkt"))

@ -1,30 +0,0 @@
#lang br
(require "misc.rkt" "line.rkt")
(provide b-for b-next)
(define thunk-table (make-hasheq))
(define-macro-cases b-for
[(_ LOOP-ID START END) #'(b-for LOOP-ID START END 1)]
[(_ LOOP-ID START END STEP)
#'(b-let LOOP-ID (let/cc loop-cc
(hash-set! thunk-table
'LOOP-ID
(λ ()
(define next-val (+ LOOP-ID STEP))
(if (next-val . in-closed-interval? . START END)
(loop-cc next-val)
(hash-remove! thunk-table 'LOOP-ID))))
START))])
(define (in-closed-interval? x start end)
(if (< start end)
(<= start x end)
(<= end x start)))
(define-macro (b-next LOOP-ID)
#'(begin
(unless (hash-has-key? thunk-table 'LOOP-ID)
(raise-line-error "next without for"))
(define thunk (hash-ref thunk-table 'LOOP-ID))
(thunk)))

@ -1,6 +1,6 @@
#lang br
(require "struct.rkt" "line.rkt")
(provide b-goto b-gosub b-return)
(require "struct.rkt" "line.rkt" "misc.rkt")
(provide b-goto b-gosub b-return b-for b-next)
(define (b-goto num-expr)
(raise (change-line-signal num-expr)))
@ -16,4 +16,29 @@
(unless (pair? return-stack)
(raise-line-error "return without gosub"))
(define top-return-k (pop! return-stack))
(top-return-k))
(top-return-k))
(define thunk-table (make-hasheq))
(define-macro-cases b-for
[(_ LOOP-ID START END) #'(b-for LOOP-ID START END 1)]
[(_ LOOP-ID START END STEP)
#'(b-let LOOP-ID (let/cc loop-cc
(hash-set! thunk-table
'LOOP-ID
(λ ()
(define next-val (+ LOOP-ID STEP))
(if (next-val . in-closed-interval? . START END)
(loop-cc next-val)
(hash-remove! thunk-table 'LOOP-ID))))
START))])
(define (in-closed-interval? x start end)
((if (< start end) <= >=) start x end))
(define-macro (b-next LOOP-ID)
#'(begin
(unless (hash-has-key? thunk-table 'LOOP-ID)
(raise-line-error "next without for"))
(define thunk (hash-ref thunk-table 'LOOP-ID))
(thunk)))

@ -3,6 +3,9 @@
(define-lex-abbrev digits (:+ (char-set "0123456789")))
(define (handle-tok-error tok-ok? tok-name tok-value start-pos end-pos)
(token 'ERROR tok-value))
(define basic-lexer
(lexer-srcloc
[(eof) (return-without-srcloc eof)]

@ -14,6 +14,6 @@
(define (handle-query key default)
(case key
[(color-lexer)
(dynamic-require 'basic-demo-2/colorer 'color-basic)]
(dynamic-require 'basic-demo-2/colorer 'basic-colorer)]
[else default]))
handle-query)

@ -1,8 +1,6 @@
#lang basic-demo-2
10 for a = 1 to 3
20 print a
21 for b = 103 to 101 step -1
22 print b
21 for b = 9 to 7 step -1
22 print a ; b
23 next b
30 next a
40 print "yay"
30 next a
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