Bounded Buffer Module

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Bounded Buffer Module

A Bounded Buffer is a data store that may hold a finite number of values. It behaves as a first-in first-out queue: values leave in order in which they arrive. We will develop a programming language implementation of a bounded buffer with three operations:

BufferInit - an initialisation

BufferIn, providing input to the buffer

BufferOut, accepting output from the buffer.

We must specify these operations, design , and implement them.

1. Specification

The state of a bounded buffer will include three components:

buffer: a sequences of values

size: the number of values present

maxsize: an indication of the buffer's capacity.

The sequence buffer, and the state itself, will use a generic parameter X to refer to the type of values to be stored:

===Buffer[X]=================

buffer : seq X

size : N

maxsize : N

size = # buffer

size ? maxsize

At initialization, the bounded buffer is empty: buffer is equal to the empty sequence and size is zero:

===BufferInit[X]==============

Buffer'[X]

buffer'=<>