I'll write something up, but here are some examples in the meantime. First, define a library with variables, methods, etc. just as they would appear in app/driver:
library (
author: "gopher.ny",
category: "samples",
description: "Some description",
name: "sampleTwo",
namespace: "samples",
documentationLink: "http://www.google.com/"
)
void method1() {}
Then, include library anywhere in the code with #include statement, starting at the beginning of the line (no spaces before #):
#include samples.sampleTwo
That's it, include will be substituted when app/driver/library is saved. All apps/drivers using include are recompiled when include gets a change. You can click on the download icon next to Import button to see exactly how the include gets into the source code.
Edit: #include's parameters (if one can call them that) is namespace, followed by a dot, followed by name. Names and namespaces can include letters (upper/lower case), numbers, dots, dashes, and underscores.