Version 2.x

The main method of this module logs on console debugging details about an object. Provided details includes an ordered list of dependencies, super calls, and both class-level and object-level AOP advises.

Description

Working with non-trivial inheritance chains can be puzzling. While the C3 MRO algorithm used by dcl takes care of duplicates and ordering of mixins, in some cases programmer needs to know the exact details of such linearization.

When dcl.log() prints what weaver was used for a given property, it uses names of weavers explained in dcl.chainWith(). Specifically, if a property has a weaver named:

• “before” – it was chained with dcl.chainBefore(), which uses dcl.weaverBefore.
• “after” – it was chained with dcl.chainAfter(), which uses dcl.weaverAfter.
• “super” – somewhere in its chain, an AOP advise (or a supercall) was used, which requires using dcl.weaverSuper.

Examples

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var dcl    = require("dcl/debug"),
  advise   = require("dcl/advise");

// A defines an "after" advise
var A = dcl(null, {
  declaredClass: "A",
  sleep: dcl.after(function () {
    console.log("*zzzzzzzzzzzzz*");
  })
});

// B provides an "around" method
var B = dcl(A, {
  declaredClass: "B",
  sleep: function () {
    console.log("Time to hit the pillow!");
  }
});

var george = new B();
// we add to the variable one more "after" advise
advise.after(george, "sleep", function(){
  console.log("*ZzZzZzZzZzZzZ*")
});

dcl.log(george);

The snippet above will produce a following output on console:

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*** object of class B
*** class B depends on 1 class: A
*** class B has 2 weavers: constructor: after, sleep: super
    sleep: object-level advice (before 0, after 2)

Notes

It is always a good idea to specify a property called declaredClass, which can be any readable text used to identify your “class” definition. It is used by dcl/debug facilities to provide a human-readable information. Common convention is to specify a name to reflect its logical “path”, like "dcl/debug" or "dcl/bases/Mixer".