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;;; open-coding primitive procedures | |
;; Copyright (C) 2009, 2010, 2011, 2012 Free Software Foundation, Inc. | |
;;;; This library is free software; you can redistribute it and/or | |
;;;; modify it under the terms of the GNU Lesser General Public | |
;;;; License as published by the Free Software Foundation; either | |
;;;; version 3 of the License, or (at your option) any later version. | |
;;;; | |
;;;; This library is distributed in the hope that it will be useful, | |
;;;; but WITHOUT ANY WARRANTY; without even the implied warranty of | |
;;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
;;;; Lesser General Public License for more details. | |
;;;; | |
;;;; You should have received a copy of the GNU Lesser General Public | |
;;;; License along with this library; if not, write to the Free Software | |
;;;; Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA | |
;;; Code: | |
(define-module (language tree-il primitives) | |
#:use-module (system base pmatch) | |
#:use-module (ice-9 match) | |
#:use-module (rnrs bytevectors) | |
#:use-module (system base syntax) | |
#:use-module (language tree-il) | |
#:use-module (srfi srfi-4) | |
#:use-module (srfi srfi-16) | |
#:export (resolve-primitives! add-interesting-primitive! | |
expand-primitives! | |
effect-free-primitive? effect+exception-free-primitive? | |
constructor-primitive? accessor-primitive? | |
singly-valued-primitive? bailout-primitive? | |
negate-primitive)) | |
;; When adding to this, be sure to update *multiply-valued-primitives* | |
;; if appropriate. | |
(define *interesting-primitive-names* | |
'(apply @apply | |
call-with-values @call-with-values | |
call-with-current-continuation @call-with-current-continuation | |
call/cc | |
dynamic-wind | |
@dynamic-wind | |
values | |
eq? eqv? equal? | |
memq memv | |
= < > <= >= zero? positive? negative? | |
+ * - / 1- 1+ quotient remainder modulo | |
ash logand logior logxor lognot | |
not | |
pair? null? list? symbol? vector? string? struct? number? char? | |
complex? real? rational? inf? nan? integer? exact? inexact? even? odd? | |
char<? char<=? char>=? char>? | |
integer->char char->integer number->string string->number | |
acons cons cons* | |
list vector | |
car cdr | |
set-car! set-cdr! | |
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 | |
vector-ref vector-set! | |
variable-ref variable-set! | |
variable-bound? | |
fluid-ref fluid-set! | |
@prompt call-with-prompt @abort abort-to-prompt | |
make-prompt-tag | |
throw error scm-error | |
string-length string-ref string-set! | |
struct-vtable make-struct struct-ref struct-set! | |
bytevector-u8-ref bytevector-u8-set! | |
bytevector-s8-ref bytevector-s8-set! | |
u8vector-ref u8vector-set! s8vector-ref s8vector-set! | |
bytevector-u16-ref bytevector-u16-set! | |
bytevector-u16-native-ref bytevector-u16-native-set! | |
bytevector-s16-ref bytevector-s16-set! | |
bytevector-s16-native-ref bytevector-s16-native-set! | |
u16vector-ref u16vector-set! s16vector-ref s16vector-set! | |
bytevector-u32-ref bytevector-u32-set! | |
bytevector-u32-native-ref bytevector-u32-native-set! | |
bytevector-s32-ref bytevector-s32-set! | |
bytevector-s32-native-ref bytevector-s32-native-set! | |
u32vector-ref u32vector-set! s32vector-ref s32vector-set! | |
bytevector-u64-ref bytevector-u64-set! | |
bytevector-u64-native-ref bytevector-u64-native-set! | |
bytevector-s64-ref bytevector-s64-set! | |
bytevector-s64-native-ref bytevector-s64-native-set! | |
u64vector-ref u64vector-set! s64vector-ref s64vector-set! | |
bytevector-ieee-single-ref bytevector-ieee-single-set! | |
bytevector-ieee-single-native-ref bytevector-ieee-single-native-set! | |
bytevector-ieee-double-ref bytevector-ieee-double-set! | |
bytevector-ieee-double-native-ref bytevector-ieee-double-native-set! | |
f32vector-ref f32vector-set! f64vector-ref f64vector-set!)) | |
(define (add-interesting-primitive! name) | |
(hashq-set! *interesting-primitive-vars* | |
(or (module-variable (current-module) name) | |
(error "unbound interesting primitive" name)) | |
name)) | |
(define *interesting-primitive-vars* (make-hash-table)) | |
(for-each add-interesting-primitive! *interesting-primitive-names*) | |
(define *primitive-constructors* | |
;; Primitives that return a fresh object. | |
'(acons cons cons* list vector make-struct make-struct/no-tail | |
make-prompt-tag)) | |
(define *primitive-accessors* | |
;; Primitives that are pure, but whose result depends on the mutable | |
;; memory pointed to by their operands. | |
'(vector-ref | |
car cdr | |
memq memv | |
struct-ref | |
string-ref | |
bytevector-u8-ref bytevector-s8-ref | |
bytevector-u16-ref bytevector-u16-native-ref | |
bytevector-s16-ref bytevector-s16-native-ref | |
bytevector-u32-ref bytevector-u32-native-ref | |
bytevector-s32-ref bytevector-s32-native-ref | |
bytevector-u64-ref bytevector-u64-native-ref | |
bytevector-s64-ref bytevector-s64-native-ref | |
bytevector-ieee-single-ref bytevector-ieee-single-native-ref | |
bytevector-ieee-double-ref bytevector-ieee-double-native-ref)) | |
(define *effect-free-primitives* | |
`(values | |
eq? eqv? equal? | |
= < > <= >= zero? positive? negative? | |
ash logand logior logxor lognot | |
+ * - / 1- 1+ quotient remainder modulo | |
not | |
pair? null? list? symbol? vector? struct? string? number? char? | |
complex? real? rational? inf? nan? integer? exact? inexact? even? odd? | |
char<? char<=? char>=? char>? | |
integer->char char->integer number->string string->number | |
struct-vtable | |
string-length | |
;; These all should get expanded out by expand-primitives!. | |
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 | |
,@*primitive-constructors* | |
,@*primitive-accessors*)) | |
;; Like *effect-free-primitives* above, but further restricted in that they | |
;; cannot raise exceptions. | |
(define *effect+exception-free-primitives* | |
'(values | |
eq? eqv? equal? | |
not | |
pair? null? list? symbol? vector? struct? string? number? char? | |
acons cons cons* list vector)) | |
;; Primitives that don't always return one value. | |
(define *multiply-valued-primitives* | |
'(apply @apply | |
call-with-values @call-with-values | |
call-with-current-continuation @call-with-current-continuation | |
call/cc | |
dynamic-wind | |
@dynamic-wind | |
values | |
@prompt call-with-prompt @abort abort-to-prompt)) | |
;; Procedures that cause a nonlocal, non-resumable abort. | |
(define *bailout-primitives* | |
'(throw error scm-error)) | |
;; Negatable predicates. | |
(define *negatable-primitives* | |
'((even? . odd?) | |
(exact? . inexact?) | |
;; (< <= > >=) are not negatable because of NaNs. | |
(char<? . char>=?) | |
(char>? . char<=?))) | |
(define *effect-free-primitive-table* (make-hash-table)) | |
(define *effect+exceptions-free-primitive-table* (make-hash-table)) | |
(define *multiply-valued-primitive-table* (make-hash-table)) | |
(define *bailout-primitive-table* (make-hash-table)) | |
(define *negatable-primitive-table* (make-hash-table)) | |
(for-each (lambda (x) | |
(hashq-set! *effect-free-primitive-table* x #t)) | |
*effect-free-primitives*) | |
(for-each (lambda (x) | |
(hashq-set! *effect+exceptions-free-primitive-table* x #t)) | |
*effect+exception-free-primitives*) | |
(for-each (lambda (x) | |
(hashq-set! *multiply-valued-primitive-table* x #t)) | |
*multiply-valued-primitives*) | |
(for-each (lambda (x) | |
(hashq-set! *bailout-primitive-table* x #t)) | |
*bailout-primitives*) | |
(for-each (lambda (x) | |
(hashq-set! *negatable-primitive-table* (car x) (cdr x)) | |
(hashq-set! *negatable-primitive-table* (cdr x) (car x))) | |
*negatable-primitives*) | |
(define (constructor-primitive? prim) | |
(memq prim *primitive-constructors*)) | |
(define (accessor-primitive? prim) | |
(memq prim *primitive-accessors*)) | |
(define (effect-free-primitive? prim) | |
(hashq-ref *effect-free-primitive-table* prim)) | |
(define (effect+exception-free-primitive? prim) | |
(hashq-ref *effect+exceptions-free-primitive-table* prim)) | |
(define (singly-valued-primitive? prim) | |
(not (hashq-ref *multiply-valued-primitive-table* prim))) | |
(define (bailout-primitive? prim) | |
(hashq-ref *bailout-primitive-table* prim)) | |
(define (negate-primitive prim) | |
(hashq-ref *negatable-primitive-table* prim)) | |
(define (resolve-primitives! x mod) | |
(post-order! | |
(lambda (x) | |
(record-case x | |
((<toplevel-ref> src name) | |
(and=> (hashq-ref *interesting-primitive-vars* | |
(module-variable mod name)) | |
(lambda (name) (make-primitive-ref src name)))) | |
((<module-ref> src mod name public?) | |
(and=> (and=> (resolve-module mod) | |
(if public? | |
module-public-interface | |
identity)) | |
(lambda (m) | |
(and=> (hashq-ref *interesting-primitive-vars* | |
(module-variable m name)) | |
(lambda (name) | |
(make-primitive-ref src name)))))) | |
(else #f))) | |
x)) | |
(define *primitive-expand-table* (make-hash-table)) | |
(define (expand-primitives! x) | |
(pre-order! | |
(lambda (x) | |
(record-case x | |
((<application> src proc args) | |
(and (primitive-ref? proc) | |
(let ((expand (hashq-ref *primitive-expand-table* | |
(primitive-ref-name proc)))) | |
(and expand (apply expand src args))))) | |
(else #f))) | |
x)) | |
;;; I actually did spend about 10 minutes trying to redo this with | |
;;; syntax-rules. Patches appreciated. | |
;;; | |
(define-macro (define-primitive-expander sym . clauses) | |
(define (inline-args args) | |
(let lp ((in args) (out '())) | |
(cond ((null? in) `(list ,@(reverse out))) | |
((symbol? in) `(cons* ,@(reverse out) ,in)) | |
((pair? (car in)) | |
(lp (cdr in) | |
(cons (if (eq? (caar in) 'quote) | |
`(make-const src ,@(cdar in)) | |
`(make-application src (make-primitive-ref src ',(caar in)) | |
,(inline-args (cdar in)))) | |
out))) | |
((symbol? (car in)) | |
;; assume it's locally bound | |
(lp (cdr in) (cons (car in) out))) | |
((self-evaluating? (car in)) | |
(lp (cdr in) (cons `(make-const src ,(car in)) out))) | |
(else | |
(error "what what" (car in)))))) | |
(define (consequent exp) | |
(cond | |
((pair? exp) | |
(pmatch exp | |
((if ,test ,then ,else) | |
`(if ,test | |
,(consequent then) | |
,(consequent else))) | |
(else | |
`(make-application src (make-primitive-ref src ',(car exp)) | |
,(inline-args (cdr exp)))))) | |
((symbol? exp) | |
;; assume locally bound | |
exp) | |
((number? exp) | |
`(make-const src ,exp)) | |
((not exp) | |
;; failed match | |
#f) | |
(else (error "bad consequent yall" exp)))) | |
`(hashq-set! *primitive-expand-table* | |
',sym | |
(match-lambda* | |
,@(let lp ((in clauses) (out '())) | |
(if (null? in) | |
(reverse (cons '(_ #f) out)) | |
(lp (cddr in) | |
(cons `((src . ,(car in)) | |
,(consequent (cadr in))) | |
out))))))) | |
(define-primitive-expander zero? (x) | |
(= x 0)) | |
(define-primitive-expander positive? (x) | |
(> x 0)) | |
(define-primitive-expander negative? (x) | |
(< x 0)) | |
;; FIXME: All the code that uses `const?' is redundant with `peval'. | |
(define-primitive-expander + | |
() 0 | |
(x) (values x) | |
(x y) (if (and (const? y) (eqv? (const-exp y) 1)) | |
(1+ x) | |
(if (and (const? y) (eqv? (const-exp y) -1)) | |
(1- x) | |
(if (and (const? x) (eqv? (const-exp x) 1)) | |
(1+ y) | |
(if (and (const? x) (eqv? (const-exp x) -1)) | |
(1- y) | |
(+ x y))))) | |
(x y z ... last) (+ (+ x y . z) last)) | |
(define-primitive-expander * | |
() 1 | |
(x) (values x) | |
(x y z ... last) (* (* x y . z) last)) | |
(define-primitive-expander - | |
(x) (- 0 x) | |
(x y) (if (and (const? y) (eqv? (const-exp y) 1)) | |
(1- x) | |
(- x y)) | |
(x y z ... last) (- (- x y . z) last)) | |
(define-primitive-expander / | |
(x) (/ 1 x) | |
(x y z ... last) (/ (/ x y . z) last)) | |
(define-primitive-expander logior | |
() 0 | |
(x) (logior x 0) | |
(x y) (logior x y) | |
(x y z ... last) (logior (logior x y . z) last)) | |
(define-primitive-expander logand | |
() -1 | |
(x) (logand x -1) | |
(x y) (logand x y) | |
(x y z ... last) (logand (logand x y . z) last)) | |
(define-primitive-expander caar (x) (car (car x))) | |
(define-primitive-expander cadr (x) (car (cdr x))) | |
(define-primitive-expander cdar (x) (cdr (car x))) | |
(define-primitive-expander cddr (x) (cdr (cdr x))) | |
(define-primitive-expander caaar (x) (car (car (car x)))) | |
(define-primitive-expander caadr (x) (car (car (cdr x)))) | |
(define-primitive-expander cadar (x) (car (cdr (car x)))) | |
(define-primitive-expander caddr (x) (car (cdr (cdr x)))) | |
(define-primitive-expander cdaar (x) (cdr (car (car x)))) | |
(define-primitive-expander cdadr (x) (cdr (car (cdr x)))) | |
(define-primitive-expander cddar (x) (cdr (cdr (car x)))) | |
(define-primitive-expander cdddr (x) (cdr (cdr (cdr x)))) | |
(define-primitive-expander caaaar (x) (car (car (car (car x))))) | |
(define-primitive-expander caaadr (x) (car (car (car (cdr x))))) | |
(define-primitive-expander caadar (x) (car (car (cdr (car x))))) | |
(define-primitive-expander caaddr (x) (car (car (cdr (cdr x))))) | |
(define-primitive-expander cadaar (x) (car (cdr (car (car x))))) | |
(define-primitive-expander cadadr (x) (car (cdr (car (cdr x))))) | |
(define-primitive-expander caddar (x) (car (cdr (cdr (car x))))) | |
(define-primitive-expander cadddr (x) (car (cdr (cdr (cdr x))))) | |
(define-primitive-expander cdaaar (x) (cdr (car (car (car x))))) | |
(define-primitive-expander cdaadr (x) (cdr (car (car (cdr x))))) | |
(define-primitive-expander cdadar (x) (cdr (car (cdr (car x))))) | |
(define-primitive-expander cdaddr (x) (cdr (car (cdr (cdr x))))) | |
(define-primitive-expander cddaar (x) (cdr (cdr (car (car x))))) | |
(define-primitive-expander cddadr (x) (cdr (cdr (car (cdr x))))) | |
(define-primitive-expander cdddar (x) (cdr (cdr (cdr (car x))))) | |
(define-primitive-expander cddddr (x) (cdr (cdr (cdr (cdr x))))) | |
(define-primitive-expander cons* | |
(x) (values x) | |
(x y) (cons x y) | |
(x y . rest) (cons x (cons* y . rest))) | |
(define-primitive-expander acons (x y z) | |
(cons (cons x y) z)) | |
(define-primitive-expander apply (f a0 . args) | |
(@apply f a0 . args)) | |
(define-primitive-expander call-with-values (producer consumer) | |
(@call-with-values producer consumer)) | |
(define-primitive-expander call-with-current-continuation (proc) | |
(@call-with-current-continuation proc)) | |
(define-primitive-expander call/cc (proc) | |
(@call-with-current-continuation proc)) | |
(define-primitive-expander make-struct (vtable tail-size . args) | |
(if (and (const? tail-size) | |
(let ((n (const-exp tail-size))) | |
(and (number? n) (exact? n) (zero? n)))) | |
(make-struct/no-tail vtable . args) | |
#f)) | |
(define-primitive-expander u8vector-ref (vec i) | |
(bytevector-u8-ref vec i)) | |
(define-primitive-expander u8vector-set! (vec i x) | |
(bytevector-u8-set! vec i x)) | |
(define-primitive-expander s8vector-ref (vec i) | |
(bytevector-s8-ref vec i)) | |
(define-primitive-expander s8vector-set! (vec i x) | |
(bytevector-s8-set! vec i x)) | |
(define-primitive-expander u16vector-ref (vec i) | |
(bytevector-u16-native-ref vec (* i 2))) | |
(define-primitive-expander u16vector-set! (vec i x) | |
(bytevector-u16-native-set! vec (* i 2) x)) | |
(define-primitive-expander s16vector-ref (vec i) | |
(bytevector-s16-native-ref vec (* i 2))) | |
(define-primitive-expander s16vector-set! (vec i x) | |
(bytevector-s16-native-set! vec (* i 2) x)) | |
(define-primitive-expander u32vector-ref (vec i) | |
(bytevector-u32-native-ref vec (* i 4))) | |
(define-primitive-expander u32vector-set! (vec i x) | |
(bytevector-u32-native-set! vec (* i 4) x)) | |
(define-primitive-expander s32vector-ref (vec i) | |
(bytevector-s32-native-ref vec (* i 4))) | |
(define-primitive-expander s32vector-set! (vec i x) | |
(bytevector-s32-native-set! vec (* i 4) x)) | |
(define-primitive-expander u64vector-ref (vec i) | |
(bytevector-u64-native-ref vec (* i 8))) | |
(define-primitive-expander u64vector-set! (vec i x) | |
(bytevector-u64-native-set! vec (* i 8) x)) | |
(define-primitive-expander s64vector-ref (vec i) | |
(bytevector-s64-native-ref vec (* i 8))) | |
(define-primitive-expander s64vector-set! (vec i x) | |
(bytevector-s64-native-set! vec (* i 8) x)) | |
(define-primitive-expander f32vector-ref (vec i) | |
(bytevector-ieee-single-native-ref vec (* i 4))) | |
(define-primitive-expander f32vector-set! (vec i x) | |
(bytevector-ieee-single-native-set! vec (* i 4) x)) | |
(define-primitive-expander f32vector-ref (vec i) | |
(bytevector-ieee-single-native-ref vec (* i 4))) | |
(define-primitive-expander f32vector-set! (vec i x) | |
(bytevector-ieee-single-native-set! vec (* i 4) x)) | |
(define-primitive-expander f64vector-ref (vec i) | |
(bytevector-ieee-double-native-ref vec (* i 8))) | |
(define-primitive-expander f64vector-set! (vec i x) | |
(bytevector-ieee-double-native-set! vec (* i 8) x)) | |
(define-primitive-expander f64vector-ref (vec i) | |
(bytevector-ieee-double-native-ref vec (* i 8))) | |
(define-primitive-expander f64vector-set! (vec i x) | |
(bytevector-ieee-double-native-set! vec (* i 8) x)) | |
(define (chained-comparison-expander prim-name) | |
(case-lambda | |
((src) (make-const src #t)) | |
((src a) #f) | |
((src a b) #f) | |
((src a b . rest) | |
(let* ((prim (make-primitive-ref src prim-name)) | |
(b-sym (gensym "b")) | |
(b* (make-lexical-ref src 'b b-sym))) | |
(make-let src | |
'(b) | |
(list b-sym) | |
(list b) | |
(make-conditional src | |
(make-application src prim (list a b*)) | |
(make-application src prim (cons b* rest)) | |
(make-const src #f))))))) | |
(for-each (lambda (prim-name) | |
(hashq-set! *primitive-expand-table* prim-name | |
(chained-comparison-expander prim-name))) | |
'(< > <= >= =)) | |
;; Appropriate for use with either 'eqv?' or 'equal?'. | |
(define maybe-simplify-to-eq | |
(case-lambda | |
((src a b) | |
;; Simplify cases where either A or B is constant. | |
(define (maybe-simplify a b) | |
(and (const? a) | |
(let ((v (const-exp a))) | |
(and (or (memq v '(#f #t () #nil)) | |
(symbol? v) | |
(and (integer? v) | |
(exact? v) | |
(<= most-negative-fixnum v most-positive-fixnum))) | |
(make-application src (make-primitive-ref #f 'eq?) | |
(list a b)))))) | |
(or (maybe-simplify a b) (maybe-simplify b a))) | |
(else #f))) | |
(hashq-set! *primitive-expand-table* 'eqv? maybe-simplify-to-eq) | |
(hashq-set! *primitive-expand-table* 'equal? maybe-simplify-to-eq) | |
(hashq-set! *primitive-expand-table* | |
'dynamic-wind | |
(case-lambda | |
((src pre thunk post) | |
(let ((PRE (gensym "pre-")) | |
(THUNK (gensym "thunk-")) | |
(POST (gensym "post-"))) | |
(make-let | |
src | |
'(pre thunk post) | |
(list PRE THUNK POST) | |
(list pre thunk post) | |
(make-dynwind | |
src | |
(make-lexical-ref #f 'pre PRE) | |
(make-application #f (make-lexical-ref #f 'thunk THUNK) '()) | |
(make-lexical-ref #f 'post POST))))) | |
(else #f))) | |
(hashq-set! *primitive-expand-table* | |
'@dynamic-wind | |
(case-lambda | |
((src pre expr post) | |
(let ((PRE (gensym "pre-")) | |
(POST (gensym "post-"))) | |
(make-let | |
src | |
'(pre post) | |
(list PRE POST) | |
(list pre post) | |
(make-dynwind | |
src | |
(make-lexical-ref #f 'pre PRE) | |
expr | |
(make-lexical-ref #f 'post POST))))))) | |
(hashq-set! *primitive-expand-table* | |
'fluid-ref | |
(case-lambda | |
((src fluid) (make-dynref src fluid)) | |
(else #f))) | |
(hashq-set! *primitive-expand-table* | |
'fluid-set! | |
(case-lambda | |
((src fluid exp) (make-dynset src fluid exp)) | |
(else #f))) | |
(hashq-set! *primitive-expand-table* | |
'@prompt | |
(case-lambda | |
((src tag exp handler) | |
(let ((args-sym (gensym))) | |
(make-prompt | |
src tag exp | |
;; If handler itself is a lambda, the inliner can do some | |
;; trickery here. | |
(make-lambda-case | |
(tree-il-src handler) '() #f 'args #f '() (list args-sym) | |
(make-application #f (make-primitive-ref #f 'apply) | |
(list handler | |
(make-lexical-ref #f 'args args-sym))) | |
#f)))) | |
(else #f))) | |
(hashq-set! *primitive-expand-table* | |
'call-with-prompt | |
(case-lambda | |
((src tag thunk handler) | |
(let ((handler-sym (gensym)) | |
(args-sym (gensym))) | |
(make-let | |
src '(handler) (list handler-sym) (list handler) | |
(make-prompt | |
src tag (make-application #f thunk '()) | |
;; If handler itself is a lambda, the inliner can do some | |
;; trickery here. | |
(make-lambda-case | |
(tree-il-src handler) '() #f 'args #f '() (list args-sym) | |
(make-application | |
#f (make-primitive-ref #f 'apply) | |
(list (make-lexical-ref #f 'handler handler-sym) | |
(make-lexical-ref #f 'args args-sym))) | |
#f))))) | |
(else #f))) | |
(hashq-set! *primitive-expand-table* | |
'@abort | |
(case-lambda | |
((src tag tail-args) | |
(make-abort src tag '() tail-args)) | |
(else #f))) | |
(hashq-set! *primitive-expand-table* | |
'abort-to-prompt | |
(case-lambda | |
((src tag . args) | |
(make-abort src tag args (make-const #f '()))) | |
(else #f))) | |