From 5a27469dcec566980f65a083bf85b69828cb514b Mon Sep 17 00:00:00 2001
From: Sergiu Ivanov <sivanov@colimite.fr>
Date: Sun, 23 Feb 2020 09:00:54 +0100
Subject: [PATCH] utils: Slightly streamline extract-symbols with match.

---
 utils.rkt | 9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

diff --git a/utils.rkt b/utils.rkt
index 7dc9ca9..59f717d 100644
--- a/utils.rkt
+++ b/utils.rkt
@@ -135,11 +135,10 @@
 ;;; Produces a list of symbols appearing in the quoted expression
 ;;; passed in the first argument.
 (define (extract-symbols form)
-  (cond
-    [(symbol? form)
-     (list form)]
-    [(list? form)
-     (flatten (for/list ([x form]) (extract-symbols x)))]
+  (match form
+    [(? symbol?) (list form)]
+    [(? list?) (flatten (for/list ([x form])
+                          (extract-symbols x)))]
     [else '()]))