1 files changed, 22 insertions, 0 deletions
diff --git a/examples/functions/isnum2 b/examples/functions/isnum2
new file mode 100644
index 0000000..e2e7a5f
--- /dev/null
+++ b/examples/functions/isnum2
@@ -0,0 +1,22 @@
+isnum2()
+{
+	case "$1" in
+	'[-+]' | '')	return 1;;	# empty or bare `-' or `+'
+	[-+]*[!0-9]*)	return 1;;	# non-digit with leading sign
+	[-+]*)		return 0;;	# OK
+	*[!0-9]*)	return 1;;	# non-digit
+	*)		return 0;;	# OK
+	esac
+}
+
+# this one handles floating point
+isnum3()
+{
+	case "$1" in
+	'')		return 1;;	# empty
+	*[!0-9.+-]*)	return 1;;	# non-digit, +, -, or .
+	*?[-+]*)	return 1;;	# sign as second or later char
+	*.*.*)		return 1;;	# multiple decimal points
+	*)		return 0;;	# OK
+	esac
+}