Computation scrapbooks of Emacs Lisp runtime state

Abstract

Snapshots of general purpose computation states have found important but limited special purpose uses (e.g. UNIX cores and Smalltalk images). A prototype system is presented for exploring additional uses for computation snapshots in the writing, debugging, testing and documenting of computer programs. These uses center on a Computation Scrapbook, which allows complete copies of program runtime states to be easily saved, organized, and restored. Emphasis is given for using multiple snapshots to benefit intermediate level programmers who have yet to acquire the skills to be comfortable with the intermediate, changing, and mostly invisible nature of computation state. The current system allows snapshots of Emacs Lisp runtime states to be used as context for code documentation, initial and goal states for test cases, and examples for general purpose programming by demonstration.