Short version appeared in * Proc. of the Conference on
Foundations of Software Technology and Theoretical Computer
Science*, pages 24-40, Bombay, India, 1993. Springer-Verlag
LNCS 761.

** Abstract.**
We introduce an extension of lambda-calculus, called
label-selective lambda-calculus, in which arguments of functions are
selected by labels. The set of labels includes numeric postions as
well as symbolic keywords. While the latter enjoy free commutation,
the former must comply with relative precedence in order to preserve
currying. This extension of lambda-calculus is conservative in the
sense that when the set of labels is the singleton {1}, it coincides
with lambda-calculus. The main result of this paper is that the
label-selective lambda-calculus is confluent. In other words, argument
selection and reduction commute.

** Keywords.** Lambda-calculus, record calculus, concurrency,
communication.

The journal version is available in DVI format. (50505 bytes).

The conference paper is in A4 Postscript format (65159 bytes).

JG 96.1.31