Processes branch

The processes branch of muSE has now reached a fair degree of completeness. This post documents the facilities available as of version 82, whose snapshot is available in the tag v0.2cp. I intend to make the processes branch the main trunk when the functionality is a bit more tested.

The processes branch implements a few significant features over and above the standard muSE engine on the trunk -

Processes

A simple implementation of Erlang style message passing processes in order to express concurrent computations. Primitives added are spawn, receive, atomic and run.

Process-local continuations

Continuation support modified to work within a process. Continuation invocation across process boundaries is forbidden. No new primitives.

Process-aware networking

muSE had some simple s-expr based communication functions all along. This branch now has these functions process aware - i.e. reading from a network port will not stall processes. A polling mechanism (which is invisble at the scheme-level) is used to handle all connections.

Resumable exception mechanism

New primitives try and raise provide the means to raise, handle and resume exceptional conditions. This is something muSE had been lacking all along and was badly needed.

Static guarded patterns (minor)