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Language/OS - Multiplatform Resource Library
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LANGUAGE OS.iso
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t3_1
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encorsrc.lha
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encore_sources
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sys
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sp_form.t
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1988-05-02
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(herald special_form
(env tsys))
;;; Needs PATTERN
(define (make-syntax-descriptor id predicate)
(object nil
((syntax-descriptor? self) t)
((identification self) id)
((print self stream)
(print-syntax-descriptor self stream))
((syntax-check-predicate self) predicate)))
(define (print-syntax-descriptor self port)
(let ((id (identification self)))
(cond ((eq? self (syntax-table-entry standard-syntax-table id))
(format port "#[Syntax~_~S]" id))
;; Temporary kludge - no JOIN.
((or (eq? self 'quasiquote)
(eq? self 'unquote)
(eq? self 'unquote-splicing))
(format port "#[Internal-syntax~_~S]" id))
(else
;++ fix this
(format port "#{Syntax~_~S~_~S}"
(object-hash self) id)))))
;;; Used only by EVAL, this procedure in the process of being phased out.
(define (obtain-syntax-table-entry table symbol spect)
(ignore spect)
(cond ((syntax-table-entry table symbol)
=> identity)
(else
(error "unknown special form ~S" symbol))))
;;; All the special forms
;;; OBJECT is still a macro for the interpreter and thus it is commented out
;;; below.
(define-local-syntax (define-special-form form)
(let ((pattern (if (null? (cdr form)) 'null? (cdr form))))
`(*define-syntax t-implementation-env
',(car form)
(make-syntax-descriptor ',(car form)
(pattern-predicate ,pattern)))))
;;; (QUOTE THING)
;;; (LAMBDA (VARS) . FORMS)
;;; (CALL PROC . ARGS)
;;; (BLOCK . FORMS)
;;; (SET-VARIABLE-VALUE ID VAL)
;;; (DEFINE-VARIABLE-VALUE ID VAL)
;;; (LSET-VARIABLE-VALUE ID VAL)
;;; (VAR-LOCATIVE ID)
;;; (DECLARE KEY . STUFF)
;;; (PRIMOP ID () . METHODS) or (PRIMOP ID (FORMALS) (METHODS) . METHODS)
;;; (IF TEST CONSEQUENT . MAYBE-ALTERNATE)
;;; (LABELS (SPECS) . FORMS)
;;; (DEFINE-LOCAL-SYNTAX ID VALUE)
;;; (DEFINE-LOCAL-SYNTAX (ID . VARS) . FORMS)
;;; (LET-SYNTAX (SPECS) . FORMS)
;;; (OBJECT PROC . METHODS)
;;; (THE-ENVIRONMENT)
;;; (LOCALE ID . FORMS)
(define-special-form (quote #f))
(define-special-form (lambda formals-list? . (+ #f)))
(define-special-form (call . (+ #f)))
(define-special-form (block . (+ #f)))
(define-special-form (set-variable-value symbol? #f))
(define-special-form (define-variable-value symbol? #f))
(define-special-form (lset-variable-value symbol? #f))
(define-special-form (var-locative symbol?))
(define-special-form (declare symbol? . (* #f)))
(define-special-form (primop symbol? . (| (null? . (* valid-method-form?))
((+ symbol?)
(* valid-method-form?)
. (* valid-method-form?)))))
(define-special-form (if #f #f . (| null? (#f))))
(define-special-form (labels (* valid-binding-spec?) . (+ #f)))
(define-special-form (define-local-syntax . valid-binding-spec?))
(define-special-form (let-syntax (* valid-binding-spec?) . (+ #f)))
(define-special-form (object #f . (* valid-method-form?)))
(define-special-form (the-environment))
(define-special-form (locale identifier? . (* #f)))
(define-special-form
(define-foreign symbol?
(symbol? . (* (foreign-parameter-spec?
foreign-representation-spec?
. (| null? symbol?))))
symbol?))
;;; Obsolete or questionable
(define-special-form (bound? symbol?))
(define-special-form (variable-value symbol?))
(define-special-form (named-lambda symbol? formals-list? . (+ #f)))
;;; Useful predicates - where to put them?
(define (identifier? x)
(or (not x)
(symbol? x)))
(define (formals-list? l)
(iterate loop ((l l))
(cond ((null? l) t)
((atom? l)
(identifier? l))
((identifier? (car l))
(loop (cdr l)))
(else nil))))
;;; BINDING-SPEC == (ID VALUE) or ((ID . VARS) . FORMS)
(define valid-binding-spec?
(pattern-predicate (| (symbol? #f)
((symbol? . formals-list?)
. (+ #f)))))
;;; METHOD == ((OP SELF-ID . IDS) . FORMS)
;;; where SELF-ID == ID or (SELF OBJ)
(define valid-method-form?
(let ((self-var? (pattern-predicate
(| identifier?
(identifier? identifier?)))))
(pattern-predicate ((#f self-var? . formals-list?) . (+ #f)))))
;;; Predicates for DEFINE-FOREIGN
(define (foreign-parameter-spec? obj)
(memq? obj '(IN OUT IN/OUT VAR IGNORE)))
(define (foreign-representation-spec? obj)
(memq? obj '(rep/integer
rep/integer-8-s
rep/integer-8-u
rep/integer-16-s
rep/integer-16-u
rep/char
rep/value
rep/extend
rep/extend-pointer
rep/string
rep/string-pointer
rep/pointer
rep/double)))
(define (foreign-return-spec? obj)
(or (foreign-representation-spec? obj)
(eq? obj 'rep/address)
(eq? obj 'ignore)))