diff options
-rw-r--r-- | module/ice-9/boot-9.scm | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/module/ice-9/boot-9.scm b/module/ice-9/boot-9.scm index 73d897c41..47f0ead60 100644 --- a/module/ice-9/boot-9.scm +++ b/module/ice-9/boot-9.scm @@ -2872,7 +2872,9 @@ module '(ice-9 q) '(make-q q-length))}." (make-struct <parameter> 0 (case-lambda (() (fluid-ref fluid)) - ((x) (fluid-set! fluid (conv x)))) + ((x) (let ((prev (fluid-ref fluid))) + (fluid-set! fluid (conv x)) + prev))) fluid conv))) (define (parameter? x) |