A distributed data structure is an object which permits many producers to augment or modify its contents, and many consumers simultaneously to access its component elements. Synchronization is implicit in data structure access: a process that requests an element which has not yet been generated blocks until a producer creates it. In this paper, we describe a parallel programming language (called T S) whose fundamental communication device is a significant generalization of the tuple-space distributed data structure found in the Linda coordination language[6]. Our sequential base language is a dialect of Scheme[19]. Beyond the fact that T S is derived by incorporating a tuple-space coordination language into a higher-order computation language (i.e., Scheme), T S differs from other tuple-space languages in two important ways: ffl Tuple-spaces are first-class objects. They may be dynamically created, bound to names, passed as arguments to (or returned as results from) functions, and b...

. We describe a parallel object-oriented dialect of Scheme called ts/scheme that provides a simple and expressive interface for building asynchronous parallel programs. The main component in ts/scheme's coordination framework is an abstraction that serves the role of a distributed data structure. Distributed data structures are an extension of conventional data structures insofar as many tasks may simultaneously access and update their contents according to a well-defined serialization protocol. The semantics of these structures also specifies that consumers which attempt to access an as-of-yet undefined element are to block until a producer provides a value. ts/scheme permits the construction of two basic kinds of distributed data structures, those accessed by content, and those accessed by name. These structures can be further specialized and composed to yield a number of other synchronization abstractions. Our intention is to provide an efficient medium for expressing concurrency a...