(append (hashq-ref %cond-expand-table mod '())
features)))))
-(define-macro (cond-expand clause . clauses)
-
- (let ((clauses (cons clause clauses))
- (syntax-error (lambda (cl)
- (error "invalid clause in `cond-expand'" cl))))
- (letrec
- ((test-clause
- (lambda (clause)
- (cond
- ((symbol? clause)
- (or (memq clause %cond-expand-features)
- (let lp ((uses (module-uses (current-module))))
- (if (pair? uses)
- (or (memq clause
- (hashq-ref %cond-expand-table (car uses) '()))
- (lp (cdr uses)))
- #f))))
- ((pair? clause)
+(define cond-expand
+ (procedure->memoizing-macro
+ (lambda (exp env)
+ (let ((clauses (cdr exp))
+ (syntax-error (lambda (cl)
+ (error "invalid clause in `cond-expand'" cl))))
+ (letrec
+ ((test-clause
+ (lambda (clause)
(cond
- ((eq? 'and (car clause))
- (let lp ((l (cdr clause)))
- (cond ((null? l)
- #t)
- ((pair? l)
- (and (test-clause (car l)) (lp (cdr l))))
- (else
- (syntax-error clause)))))
- ((eq? 'or (car clause))
- (let lp ((l (cdr clause)))
- (cond ((null? l)
- #f)
- ((pair? l)
- (or (test-clause (car l)) (lp (cdr l))))
- (else
- (syntax-error clause)))))
- ((eq? 'not (car clause))
- (cond ((not (pair? (cdr clause)))
- (syntax-error clause))
- ((pair? (cddr clause))
- ((syntax-error clause))))
- (not (test-clause (cadr clause))))
- (else
- (syntax-error clause))))
- (else
- (syntax-error clause))))))
- (let lp ((c clauses))
- (cond
- ((null? c)
- (error "Unfulfilled `cond-expand'"))
- ((not (pair? c))
- (syntax-error c))
- ((not (pair? (car c)))
- (syntax-error (car c)))
- ((test-clause (caar c))
- `(begin ,@(cdar c)))
- ((eq? (caar c) 'else)
- (if (pair? (cdr c))
+ ((symbol? clause)
+ (or (memq clause %cond-expand-features)
+ (let lp ((uses (module-uses (env-module env))))
+ (if (pair? uses)
+ (or (memq clause
+ (hashq-ref %cond-expand-table
+ (car uses) '()))
+ (lp (cdr uses)))
+ #f))))
+ ((pair? clause)
+ (cond
+ ((eq? 'and (car clause))
+ (let lp ((l (cdr clause)))
+ (cond ((null? l)
+ #t)
+ ((pair? l)
+ (and (test-clause (car l)) (lp (cdr l))))
+ (else
+ (syntax-error clause)))))
+ ((eq? 'or (car clause))
+ (let lp ((l (cdr clause)))
+ (cond ((null? l)
+ #f)
+ ((pair? l)
+ (or (test-clause (car l)) (lp (cdr l))))
+ (else
+ (syntax-error clause)))))
+ ((eq? 'not (car clause))
+ (cond ((not (pair? (cdr clause)))
+ (syntax-error clause))
+ ((pair? (cddr clause))
+ ((syntax-error clause))))
+ (not (test-clause (cadr clause))))
+ (else
+ (syntax-error clause))))
+ (else
+ (syntax-error clause))))))
+ (let lp ((c clauses))
+ (cond
+ ((null? c)
+ (error "Unfulfilled `cond-expand'"))
+ ((not (pair? c))
(syntax-error c))
- `(begin ,@(cdar c)))
- (else
- (lp (cdr c))))))))
+ ((not (pair? (car c)))
+ (syntax-error (car c)))
+ ((test-clause (caar c))
+ `(begin ,@(cdar c)))
+ ((eq? (caar c) 'else)
+ (if (pair? (cdr c))
+ (syntax-error c))
+ `(begin ,@(cdar c)))
+ (else
+ (lp (cdr c))))))))))
;; This procedure gets called from the startup code with a list of
;; numbers, which are the numbers of the SRFIs to be loaded on startup.