DragonFly On-Line Manual Pages
nx::next(3) nx::next(3)
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NAME
nx::next - Skip to the next most specific method implementation
SYNOPSIS
next ?arguments?
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DESCRIPTION
next ?arguments?
This command is invoked inside a method body to call the next
most specific method implementation in the list of available
methods. This list of available methods is specific to the
current method-call context. This context is set by the usage
context of nx::next (method combination vs. method-call
interception; see below). The optional arguments are the
argument values to be passed into the next most specific method
implementation. If omitted, the arguments of the current method
call are automatically forwarded. To call the next most specific
method implementation without arguments (or to suppress argument
forwarding), arguments must be set to an empty string. To pass
an empty string as a (single) argument value, protect it as a
list. The result of a call to nx::next is the result of the next
most specific method implementation. If there are no more
further applicable methods, the result of nx::next will depend
on its usage context: method combination or method-call
interception. If nx::next is used in a method body for method
combination, the result will be an empty string. If nx::next is
used in the body of a filter method for method-call
interception, the result will be an error.
When executing a method call, the NX dispatch mechanism computes
a list of applicable method implementations for the method name
requested from a given object receiving the call; in support of
method combination and method-call interception.
For method combination, the computed list contains any object-
local method implementation and any method implementations
inherited by the object from the classes in its precedence list.
Examples are overloading method implementations in the class
hierarchy of the object, as well as from mixin classes of the
object. For method-call interception, the computed list contains
the applicable filter methods, again ordered by their definition
order according to the precedence list of the called object.
To retrieve the next most specific method implementation to be
invoked by nx::current from the internally computed list, if
any, use nx::current.
COPYRIGHT
Copyright (c) 2014 Stefan Sobernig <stefan.sobernig@wu.ac.at>, Gustaf Neumann <gustaf.neumann@wu.ac.at>
next 2.0 nx::next(3)