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Diffstat (limited to 'module/ice-9/boot-9.scm')
-rw-r--r-- | module/ice-9/boot-9.scm | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/module/ice-9/boot-9.scm b/module/ice-9/boot-9.scm index dcff0ed7a..3b98aaf75 100644 --- a/module/ice-9/boot-9.scm +++ b/module/ice-9/boot-9.scm @@ -1241,6 +1241,12 @@ VALUE." (nparents (vector-length parents))) (and (not (zero? nparents)) (vector-ref parents (1- nparents))))) +(define (record-type-has-parent? rtd parent) + (or (eq? rtd parent) + (let ((parents (record-type-parents rtd)) + (nparents (vector-length (record-type-parents parent)))) + (and (< nparents (vector-length parents)) + (eq? (vector-ref parents nparents) parent))))) (define (record-type-mutable-fields rtd) (unless (record-type? rtd) |