Update plans [specification]

Update plans, are a high level language for specifying low level activities. Update plans are amenable to interpretation as declarative specifications of machine state transitions while maintaining a great deal of similarity to low level code, thus allowing for efficient compilation to executable code. The syntax and semantics of update plans are informally introduced. The second half contains a non-trivial example of their application, in which an abstract machine for a simple functional language is presented. Preliminary results for an implementation of this machine, obtained by applying a prototype update plan compiler to the specification, are also presented