racket/collects/eopl/eopl.rkt
2012-04-05 23:24:43 -04:00

216 lines
7.7 KiB
Racket

#lang racket
(require "datatype.rkt"
"private/sllgen.rkt"
mzlib/trace
mzlib/pretty)
(require (for-syntax "private/slldef.rkt"))
(provide define-datatype
cases)
;; Special def that saves a quoted value at compile time in case
;; it's needed for `sllgen:make-define-datatypes':
(define-syntax (eopl-define stx)
(syntax-case stx (quote)
[(_ name (quote def))
(identifier? (syntax name))
(syntax/loc stx
(begin
(begin-for-syntax
(hash-set! sllgen-def 'name (quote-syntax def)))
(define name (quote def))))]
[(_ . rest)
(syntax/loc stx (define . rest))]))
(provide (rename-out [eopl-define define]))
(provide (all-from-out "private/sllgen.rkt"))
(provide (rename-out [error eopl:error]
[printf eopl:printf]
[pretty-print eopl:pretty-print]
[eopl:call-with-current-continuation
call-with-current-continuation]))
;; ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;; Ugly:
;;
;; 1) `eopl:error-stop' has to be a top-level binding to be
;; mutated by client programs --- actually, the test harness ---
;; for exception handling.
;; 2) Exception jumps by the test harness are performed through
;; call/cc, not call/ec.
;;
;; Solution: use `namespace-variable-value', and create an escape
;; continuation for each nested continuation.
(define esc-cont-mark-key (gensym))
(define detect-tail-key (gensym))
(define recovering-from-error (make-parameter #f))
(define (mk-k k ek)
(lambda args
(apply (if (recovering-from-error) ek k) args)))
(define (eopl:call-with-current-continuation f)
(unless (and (procedure? f)
(procedure-arity-includes? f 1))
;; let call/cc report the error:
(call/cc f))
(let/cc k
(let ([v (gensym)]
[orig-marks (continuation-mark-set->list
(continuation-marks k)
detect-tail-key)])
(with-continuation-mark detect-tail-key v
(let ([new-marks (continuation-mark-set->list
(current-continuation-marks)
detect-tail-key)])
(if (or (null? orig-marks)
(and (pair? (cdr new-marks))
(eq? (car orig-marks) (cadr new-marks))))
;; Old mark surived => not tail wrt old call.
;; Create an escape continuation to use for
;; error escapes. Of course, we rely on the fact
;; that continuation marks are not visible to EoPL
;; programs.
(let/ec ek
(with-continuation-mark esc-cont-mark-key ek
(with-continuation-mark detect-tail-key (gensym)
(f (mk-k k ek)))))
;; Old mark replaced => tail wrt old call.
;; To preserve tail semantics for all but the first call
;; reuse `mark' instead of creating a new escape continuation:
(let ([mark (car (continuation-mark-set->list
(continuation-marks k)
esc-cont-mark-key))])
(f (mk-k k mark)))))))))
(namespace-set-variable-value! 'eopl:error-stop #f #t)
(define (install-eopl-exception-handler)
(uncaught-exception-handler
(let ([eh (uncaught-exception-handler)]
[orig-namespace (current-namespace)])
(lambda (x)
(let ([v (with-handlers ([void (lambda (x) #f)])
(parameterize ([current-namespace orig-namespace])
(namespace-variable-value 'eopl:error-stop)))])
(if v
(parameterize ([recovering-from-error #t])
(v))
(eh x)))))))
(provide install-eopl-exception-handler)
;; ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
(provide always? list-of maybe)
(define always?
(lambda (x) #t))
(define list-of
(lambda (pred . l)
(let ((all-preds (cons pred l)))
(lambda (obj)
(let loop ((obj obj) (preds '()))
(or
;; if list is empty, preds should be, too
(and (null? obj) (null? preds))
(if (null? preds)
;; if preds is empty, but list isn't, then recycle
(loop obj all-preds)
;; otherwise check and element and recur.
(and (pair? obj)
((car preds) (car obj))
(loop (cdr obj) (cdr preds))))))))))
(define maybe
(lambda (pred)
(lambda (obj)
(or (pred obj)
(eqv? obj #f)))))
;; ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
(define empty null)
(provide time ;; useful to compare implementations
collect-garbage ;; useful with `time'
empty ;; for constructor-based printing
trace untrace ;; debugging
require module ;; we allow full use of modules
only-in
prefix-in
provide ;; in case someone wants to use a module
all-defined-out
all-from-out ;; surely some subforms are missing
rename-out
make-parameter
parameterize
print-struct)
(require mzlib/transcr)
(provide unquote unquote-splicing
quote quasiquote if when unless
lambda letrec define-syntax delay let let* let-syntax letrec-syntax
and or cond case do
begin set!
=> else
(rename-out [#%plain-module-begin #%module-begin])
#%app #%datum #%top #%top-interaction
#%require #%provide #%expression
(for-syntax syntax-rules ...)
cons car cdr pair? map for-each
caar cadr cdar cddr
caaar caadr cadar caddr cdaar cdadr cddar cdddr
caaaar caaadr caadar caaddr cadaar cadadr caddar cadddr
cdaaar cdaadr cdadar cdaddr cddaar cddadr cdddar cddddr
= < > <= >= max min + - * /
abs gcd lcm exp log sin cos tan not eq?
make-string
symbol->string string->symbol make-rectangular
exact->inexact inexact->exact number->string string->number
rationalize output-port? current-input-port current-output-port current-error-port
open-input-file open-output-file close-input-port close-output-port
with-output-to-file transcript-on transcript-off flush-output
string-length string-ci<=? string-ci>=? string-append
string-fill!
string->list list->string
vector-length vector-fill!
vector->list list->vector
char-alphabetic? char-numeric? char-whitespace?
char-upper-case? char-lower-case? char->integer integer->char char-downcase
call-with-output-file call-with-input-file with-input-from-file
apply symbol?
null?
list? list length append reverse list-tail
list-ref memq memv member assq assv assoc
procedure?
number? complex? real? rational? integer? exact? inexact? zero?
positive? negative? odd? even?
quotient remainder modulo floor ceiling truncate round
numerator denominator asin acos atan sqrt
expt make-polar real-part imag-part angle magnitude input-port?
read read-char peek-char eof-object?
char-ready?
write display
newline write-char load
string? string string-ref string-set! string=? substring string-copy
string-ci=? string<? string>? string<=? string>=? string-ci<? string-ci>?
vector? make-vector vector vector-ref vector-set!
char? char=? char<? char>? char<=? char>=?
char-ci=? char-ci<? char-ci>? char-ci<=? char-ci>=?
char-upcase boolean? eqv? equal?
force
call-with-values values dynamic-wind
eval
#|
scheme-report-environment null-environment interaction-environment
|#
)