Module: ConDuxml::Link

Includes:
Instance
Defined in:
lib/con_duxml/link.rb

Overview

links are effectively aliases for an XML node that can exist anywhere outside of that node they confer referencing scope, namespace, and notifications of content changes anything contained by a link element is then dynamically linked to the target this is useful for designs where one element’s state depends on another’s or where it’s important to track a target that may not be in a fixed location

Instance Method Summary collapse

Methods included from Instance

#activate, #resolve_ref

Instance Method Details

#instantiate(&block) ⇒ Array

Returns nodes to replace this link - children by default.

Parameters:

  • block (block) —

    each child node is yielded to block if given

Returns:

  • (Array) —

    nodes to replace this link - children by default



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# File 'lib/con_duxml/link.rb', line 29

def instantiate(&block)
  resolve_ref.add_observer(self)
  block_given? ? yield(nodes.each) : nodes
end

#ref=(target) ⇒ Object 



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# File 'lib/con_duxml/link.rb', line 22

def ref=(target)
  target.extend Linkable
  @ref = target
end

#strict?(bool = nil) ⇒ true, false

Returns current value (true by default)

Parameters:

  • bool (true, false, nil) (defaults to: nil) —

    if true or false, sets @strict_or_false to this value

Returns:

  • (true, false) —

    returns current value (true by default)



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# File 'lib/con_duxml/link.rb', line 36

def strict?(bool=nil)
  bool.nil? ? @strict_or_false ||= true : @strict_or_false = bool
end

#update(type, *args) ⇒ Object

TODO rewrite this!!! at most primitive, updates need to happen when link targets split/merge or are removed

Parameters:

  • type (Symbol) —

    category i.e. class symbol of changes/errors reported

  • *args (*several_variants) —

    information needed to accurately log the event; varies by change/error class

Raises:

  • (Exception) 


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# File 'lib/con_duxml/link.rb', line 43

def update(type, *args)
  change_class = Duxml::const_get "#{type.to_s}Class".to_sym
  change_comp = change_class.new *args
  @nodes.unshift change_comp
  changed
  notify_observers(change_comp) unless change_comp.respond_to?(:error?)
  raise(Exception, change_comp.description) if strict? && type == :QualifyError
end

#valid? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/con_duxml/link.rb', line 18

def valid?
  !resolve_ref.nil?
end