Spade Language Specification

NOTE: This has been superceded by RC24897 (November 5, 200) and RC24914 (December 3, 2009)

This document defines the Spade language, version 2. Spade is a programming language for high-performance distributed stream processing systems. A Spade program describes a data flow graph, where the vertices are operator instances and the directed edges are streams. Spade is extensible by allowing users to define their own primitive operators in a native language, and by allowing users to define their own parameterizable composite operators in Spade itself. Furthermore, Spade permits users to dynamically compose independently launched streaming programs. Thanks to its generality, Spade makes it easy to express applications from a large variety of domains, including but not limited to financial trading, transportation monitoring, manufacturing control, security, healthcare, etc.