reorganizing code

original commit: f2f87e214ae5428eb6348f487ad42960683e23f8
This commit is contained in:
Eli Barzilay 2004-11-01 14:37:59 +00:00
parent 0c20f39b6b
commit 19a09f7e8d

View File

@ -70,81 +70,6 @@
[(_ name expr)
(begin (provide name) (define name expr))]))
;; ----------------------------------------------------------------------------
;; Compile-time support for fun-expanders
;; The `_fun' macro tears its input apart and reassemble it using pieces from
;; custom function types (macros). This whole deal needs some work to make it
;; play nicely with code certificates, so Matthew wrote the following code.
;; The idea is to create a define-fun-syntax which is not really a new kind of
;; a syntax transformer which should always be expanded with
;; `expand-fun-syntax'.
(begin-for-syntax
(define fun-cert-key (gensym))
(define-values (make-fun-syntax fun-syntax?
fun-syntax-proc fun-syntax-certifier)
(let-values ([(desc make pred? get set!)
(make-struct-type
'fun-syntax #f 2 0 #f '() (current-inspector) 0)])
(values make pred?
(make-struct-field-accessor get 0 'proc)
(make-struct-field-accessor get 1 'certifier))))
(define (expand-fun-syntax stx)
(let loop ([stx stx])
(define (do-expand id id?) ; id? == are we expanding an identifier?
(define v (syntax-local-value id (lambda () #f)))
(define set!-trans? (set!-transformer? v))
(define proc (if set!-trans? (set!-transformer-procedure v) v))
(if (and (fun-syntax? proc) (or (not id?) set!-trans?))
;; Do essentially the same thing that `local-expand' does.
;; First, create an "introducer" to mark introduced identifiers:
(let* ([introduce (make-syntax-introducer)]
[expanded
;; Re-introduce mark related to expansion of `_fun':
(syntax-local-introduce
;; Re-add mark specific to this expansion, cancelling
;; some marks applied before expanding (leaving only
;; introuced syntax marked)
(introduce
;; Actually expand:
(proc
;; Add mark specific to this expansion:
(introduce
;; Remove mark related to expansion of `_fun':
(syntax-local-introduce stx)))))])
;; Certify based on definition of expander, then loop
;; to continue expanding:
(loop ((fun-syntax-certifier proc)
expanded fun-cert-key introduce)))
stx))
(syntax-case stx ()
[(id . rest) (identifier? #'id) (do-expand #'id #f)]
[id (identifier? #'id) (do-expand #'id #t)]
[_else stx]))))
;; Use define-fun-syntax instead of define-syntax for forms that
;; are to be expanded by `_fun':
(provide define-fun-syntax)
(define-syntax define-fun-syntax
(syntax-rules ()
[(_ id trans)
(define-syntax id
(let* ([xformer trans]
[set!-trans? (set!-transformer? xformer)])
(unless (or (and (procedure? xformer)
(procedure-arity-includes? xformer 1))
set!-trans?)
(raise-type-error 'define-fun-syntax
"procedure (arity 1) or set!-transformer"
xformer))
(let ([f (make-fun-syntax (if set!-trans?
(set!-transformer-procedure xformer)
xformer)
;; Capture definition-time certificates:
(syntax-local-certifier))])
(if set!-trans? (make-set!-transformer f) f))))]))
;; ----------------------------------------------------------------------------
;; Getting and setting library objects
@ -245,50 +170,76 @@
(define ffi-objects-ref-table (make-hash-table))
;; ----------------------------------------------------------------------------
;; Function type
;; Compile-time support for fun-expanders
;; Creates a simple function type that can be used for callouts and callbacks,
;; optionally applying a wrapper function to modify the result primitive
;; (callouts) or the input procedure (callbacks).
(define* (_cprocedure itypes otype . wrapper)
(let ([wrapper (and (pair? wrapper) (car wrapper))])
(if wrapper
(make-ctype _fpointer
(lambda (x) (ffi-callback (wrapper x) itypes otype))
(lambda (x) (wrapper (ffi-call x itypes otype))))
(make-ctype _fpointer
(lambda (x) (ffi-callback x itypes otype))
(lambda (x) (ffi-call x itypes otype))))))
(begin-for-syntax
;; Syntax for the special _fun type:
;; (_fun [{(name ... [. name]) | name} [-> expr] ::]
;; {type | (name : type [= expr]) | ([name :] type = expr)} ...
;; -> {type | (name : type)}
;; [-> expr])
;; Usage:
;; `{(name ...) | ...} ::' specify explicit wrapper function formal arguments
;; `-> expr' can be used instead of the last expr
;; `type' input type (implies input, but see type macros next)
;; `(name : type = expr)' specify name and type, `= expr' means computed input
;; `-> type' output type (possibly with name)
;; `-> expr' specify different output, can use previous names
;; Also, see below for custom function types.
;; The `_fun' macro tears its input apart and reassemble it using pieces from
;; custom function types (macros). This whole deal needs some work to make
;; it play nicely with code certificates, so Matthew wrote the following
;; code. The idea is to create a define-fun-syntax which is not really a new
;; kind of a syntax transformer which should always be expanded with
;; `expand-fun-syntax'.
(begin-for-syntax ; utilities for _fun
;; use module-or-top-identifier=? because we use keywords like `=' and want to
;; make it possible to play with it at the toplevel
(define fun-cert-key (gensym))
(define-values (make-fun-syntax fun-syntax?
fun-syntax-proc fun-syntax-certifier)
(let-values ([(desc make pred? get set!)
(make-struct-type
'fun-syntax #f 2 0 #f '() (current-inspector) 0)])
(values make pred?
(make-struct-field-accessor get 0 'proc)
(make-struct-field-accessor get 1 'certifier))))
(define (expand-fun-syntax stx)
(let loop ([stx stx])
(define (do-expand id id?) ; id? == are we expanding an identifier?
(define v (syntax-local-value id (lambda () #f)))
(define set!-trans? (set!-transformer? v))
(define proc (if set!-trans? (set!-transformer-procedure v) v))
(if (and (fun-syntax? proc) (or (not id?) set!-trans?))
;; Do essentially the same thing that `local-expand' does.
;; First, create an "introducer" to mark introduced identifiers:
(let* ([introduce (make-syntax-introducer)]
[expanded
;; Re-introduce mark related to expansion of `_fun':
(syntax-local-introduce
;; Re-add mark specific to this expansion, cancelling
;; some marks applied before expanding (leaving only
;; introuced syntax marked)
(introduce
;; Actually expand:
(proc
;; Add mark specific to this expansion:
(introduce
;; Remove mark related to expansion of `_fun':
(syntax-local-introduce stx)))))])
;; Certify based on definition of expander, then loop
;; to continue expanding:
(loop ((fun-syntax-certifier proc)
expanded fun-cert-key introduce)))
stx))
(syntax-case stx ()
[(id . rest) (identifier? #'id) (do-expand #'id #f)]
[id (identifier? #'id) (do-expand #'id #t)]
[_else stx])))
;; use module-or-top-identifier=? because we use keywords like `=' and want
;; to make it possible to play with it at the toplevel
(define id=? module-or-top-identifier=?)
(define (split-by key args)
(let loop ([args args] [r (list '())])
(cond [(null? args) (reverse! (map reverse! r))]
[(eq? key (car args)) (loop (cdr args) (cons '() r))]
[else (set-car! r (cons (car args) (car r)))
(loop (cdr args) r)])))
(define (filtmap f l)
(let loop ([l l] [r '()])
(if (null? l)
(reverse! r)
(let ([x (f (car l))]) (loop (cdr l) (if x (cons x r) r))))))
(define (add-renamer body from to)
(with-syntax ([body body] [from from] [to to])
#'(let-syntax ([to (syntax-id-rules ()
@ -328,6 +279,58 @@
[() (and (pair? keys) keys)]
[_else #f])))))
;; Use define-fun-syntax instead of define-syntax for forms that
;; are to be expanded by `_fun':
(provide define-fun-syntax)
(define-syntax define-fun-syntax
(syntax-rules ()
[(_ id trans)
(define-syntax id
(let* ([xformer trans]
[set!-trans? (set!-transformer? xformer)])
(unless (or (and (procedure? xformer)
(procedure-arity-includes? xformer 1))
set!-trans?)
(raise-type-error 'define-fun-syntax
"procedure (arity 1) or set!-transformer"
xformer))
(let ([f (make-fun-syntax (if set!-trans?
(set!-transformer-procedure xformer)
xformer)
;; Capture definition-time certificates:
(syntax-local-certifier))])
(if set!-trans? (make-set!-transformer f) f))))]))
;; ----------------------------------------------------------------------------
;; Function type
;; Creates a simple function type that can be used for callouts and callbacks,
;; optionally applying a wrapper function to modify the result primitive
;; (callouts) or the input procedure (callbacks).
(define* (_cprocedure itypes otype . wrapper)
(let ([wrapper (and (pair? wrapper) (car wrapper))])
(if wrapper
(make-ctype _fpointer
(lambda (x) (ffi-callback (wrapper x) itypes otype))
(lambda (x) (wrapper (ffi-call x itypes otype))))
(make-ctype _fpointer
(lambda (x) (ffi-callback x itypes otype))
(lambda (x) (ffi-call x itypes otype))))))
;; Syntax for the special _fun type:
;; (_fun [{(name ... [. name]) | name} [-> expr] ::]
;; {type | (name : type [= expr]) | ([name :] type = expr)} ...
;; -> {type | (name : type)}
;; [-> expr])
;; Usage:
;; `{(name ...) | ...} ::' specify explicit wrapper function formal arguments
;; `-> expr' can be used instead of the last expr
;; `type' input type (implies input, but see type macros next)
;; `(name : type = expr)' specify name and type, `= expr' means computed input
;; `-> type' output type (possibly with name)
;; `-> expr' specify different output, can use previous names
;; Also, see below for custom function types.
(provide _fun)
(define-syntax (_fun stx)
(define (err msg . sub) (apply raise-syntax-error '_fun msg stx sub))