SRFI 89: Optional positional and named parameters

by Marc Feeley

status: final (2007-07-10)

keywords: Binding

See also SRFI 88: Keyword objects and SRFI 177: Portable keyword arguments.

Abstract

This SRFI specifies the define* and lambda* special forms. These forms extend the R5RS define and lambda special forms to simplify the use of optional positional and named parameters. Optional positional parameters, optional named parameters and required named parameters are covered by this SRFI. The formal parameter list syntax specified in this SRFI is different from the syntax used by Common Lisp and the DSSSL languages but nevertheless offers similar functionality and a nicer syntax. Formal parameter lists which conform to the R5RS syntax have the same meaning as in R5RS.