From c0917f3bc925a4bc75cb5d2078375339f021cfe6 Mon Sep 17 00:00:00 2001 From: Matthew Butterick Date: Mon, 18 Nov 2019 15:07:41 -0800 Subject: [PATCH] iterate in a way that allows #false values --- quad/quadwriter/attrs.rkt | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/quad/quadwriter/attrs.rkt b/quad/quadwriter/attrs.rkt index c48d5670..14617242 100644 --- a/quad/quadwriter/attrs.rkt +++ b/quad/quadwriter/attrs.rkt @@ -31,9 +31,8 @@ (define new-hash (make-hasheq)) (for ([(k v) (in-hash dest-hash)]) (hash-set! new-hash k v)) - (for* ([k (in-list block-attrs)] - [v (in-value (hash-ref source-hash k #f))] - #:when v) + (for ([(k v) (in-hash source-hash)] + #:when (memq k block-attrs)) (hash-set! new-hash k v)) new-hash)