Adds function numeric-only

Author: joeljuca

src/numeric-only.sh

@@ -0,0 +1,10 @@
+#!/usr/bin/env bash
+# Copyright (c) 2018 Joel Wallis Jucá <[email protected]>
+# ISC licensed
+
+# Strips all non-numeric characters from passed arguments
+function numeric-only {
+  echo -n "$@" \
+    | xargs \
+    | sed -E "s/[^0-9]+//g"
+}