- make-variable INIT #!optional GUARDprocedure
Returns a procedure whose behavior is that of a parameter, except for the fact that it is not a parameter. The closed-over value is not thread-local.
INIT is some Scheme object that meets the constraint enforced by the GUARD.
GUARD is a (procedure (*) *) returning an acceptable value for the variable. Default is identity.
Supports SRFI 17.