No one likes to read manuals to find out how to use a system. This is especially true of programming interactive applications which are both exciting and complex. Certainly good examples are helpful and here we try to collect some simple but illustrative examples of Trestle. Trestle is a library written in the Modula-3 programming language that provides portable access to windowing system functions that work across Microsoft Windows or X Windows.

Trestle is a Modula-3 library for access to the native window system. Trestle is a collection of interfaces structured around a central abstract type: a virtual bitmap terminal VBT, which represents a share of the workstation's screen, keyboard, and mouse. This abstraction makes Trestle unique and removes it from the low-level abstraction of the X Window System. The programmer can learn the Trestle abstracts and ignore the underlying reliance on X11 or Win32. Indeed, it does not matter if the X Window System or Microsoft Windows is running underneath.

A number of references for Trestle and its VBT kit are available here. The reference manual for Trestle is a DEC technical report:

Mark Manasse and Greg Nelson. Trestle Reference Manual. SRC Report 68, DEC Systems Research Center, Palo Alto, California, December 1991.
Another technical report documents VBTKit. VBTKit is another set of modules and a library that extends Trestle.
Mark Brown and James Meehan. VBTKit Reference Manual: A toolkit for Trestle. DEC Systems Research Center, Palo Alto, California, March 1993.