From b1c1eb5cf1005a95becac4c30776436bac12593d Mon Sep 17 00:00:00 2001
From: Pekka Laiho <pekka.i.laiho@gmail.com>
Date: Tue, 22 Dec 2020 10:16:41 +0700
Subject: [PATCH] add util.mad with some utility functions

---
 mad/util.mad | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)
 create mode 100644 mad/util.mad

diff --git a/mad/util.mad b/mad/util.mad
new file mode 100644
index 0000000..c80f99b
--- /dev/null
+++ b/mad/util.mad
@@ -0,0 +1,16 @@
+
+;;
+;; Generic utility functions.
+;;
+
+;; Return first item of sequence, or null if it is empty.
+(defn first-or-null (seq) (if (empty? seq) null (first seq)))
+
+;; Split string by whitespace, removing empty strings.
+(defn split-ws (s) (re-split "/[\\s]+/" s))
+
+;; Split string by whitespace into first and rest.
+;; Useful for parsing a string for command name and arguments.
+(defn str-first-rest (s)
+  (let (words (split-ws s))
+    [(first-or-null words) (tail words)]))