单身人士在JS /咖啡脚本中引用自己的优雅方式？

Question

I'm creating a module consisting of a singleton designed to store data:

context =
    c:@
    selected:
        sketch: undefined
        points: []
        edges: []
    hovered:
        points: []
        edges: []
    ###Note: Perhaps later I can make a more elegant naming scheme
    say, specifying subobjects such as context.select.sketch(<sketch>)###
    select:
        sketch: (sketch)->
            c.selected.sketch = sketch
            return
        node: (point)->
            c.selected.points.push point
    deselectAll: ->
        ###Clear all arrays ###
        c.selected.points.length = 0
        c.selected.edges.length = 0

I want select to contain methods for accessing attributes inside the selected sub-object. However, unlike a closure, I can't store this inside a named variable, and I can't access context from within context.select as this will refer to context.select

How can I establish a reference to the parent/root object for use within sub-objects?

Answer 1

I encourage you to create classes with no namespaces for improved readability. Here you are, thou:

# please use class syntax as a vessel to create singleton
# you may declare class and then call new and assign it's instance to avariable 
# or, since it's a singleton, you can do that in one line
window.Context = new class Context

# constructor function should init the object
constructor: ->
    @selected =
      sketch: undefined
      points: []
      edges: []
    @hovered =
      points: []
      edges: []

    # convenience namespace, just referring to class methods
    @select =
      sketch: @selectSketch
      node: @selectNode

  # not having namespaces adds a lot to clarity of the class
  selectSketch: (sketch) =>
    # no need to call return here
    @selected.sketch = sketch

  selectNode: (point) =>
    @selected.points.push point

  # you probably want to assign new array rather then reset the length 
  deselectAll: =>
    @selected.points = []
    @selected.edges = []