Properties of a First-Order Functional Language with Sharing

A calculus and a model for a rst-order functional language with sharing is presented. In most implementations of functional languages, argument subexpressions in a function application are shared to avoid their repeated evaluation. Recursive functions are typically implemented using graphs with cycles. Compilers for these languages sometimes employ non-left-linear and left-cyclic rules for optimizations. A Graph Rewriting System (GRS) to address these concerns is developed. It is shown that a GRS without interfering rules is connuent. Along the lines of L evy's term model for the-calculus, a semantics of such a GRS is also presented. An application of the term model to compiler optimizations is discussed.