BendDecorator

The bend can be decorated in various ways. addConstant decorates the bend's lookup to return the same instance for each bend.

graph.decorator.bends.handle.addConstant(new ConstantHandle())

addConstant with a predicate decorates the bend's lookup only to return the same instance for each bend for which the predicate returns true.

graph.decorator.bends.handle.addConstant(
  (bend) => bend.tag !== null,
  new ConstantHandle(),
)

addFactory calls the provided factory method to return a new instance of the queried type created for the given bend or for bends for which the predicate returns true, respectively:

graph.decorator.bends.handle.addFactory((bend) => new CustomHandle(bend))
graph.decorator.bends.handle.addFactory(
  (bend) => bend.tag !== null,
  (bend) => new CustomHandle(bend),
)

addWrapperFactory calls the provided factory method to return a new instance of the queried type which wraps the default implementation, once for all bends and once only for bends for which the predicate returns true.

graph.decorator.bends.handle.addWrapperFactory(
  (bend, original) => new HandleWrapper(bend!, original),
)
graph.decorator.bends.handle.addWrapperFactory(
  (bend) => bend.tag !== null,
  (bend, original) => new HandleWrapper(bend!, original),
)

Finally hide hides the default implementation by letting the lookup always return null for all bends and for bends for which the predicate returns true, respectively

graph.decorator.bends.handle.hide()
graph.decorator.bends.handle.hide((bend) => bend.tag !== null)

Each of these methods returns a IContextLookupChainLink which can be used to remove the modified behavior again:

constructor() {}

registerLookup(graph: IGraph): void {
  this.chainLink = graph.decorator.bends.handle.addFactory(
    (bend) => new CustomHandle(bend),
  )!
}

deregisterLookup(graph: IGraph): void {
  graph.decorator.bends.remove(this.chainLink)
}