Question

I am using jQuery and I am still pretty new to JavaScript. I am implementing an object as the following:

MyObject = {
  properties     : [{}],
  resetProperties: function resetProperties() { this.properties = [{}] }
};

As you can see in the above code I can reset the properties by running MyObject.resetProperties() but, in order to do that, I state two times the [{}] variable. How should I accomplish the same thing without repeating that code?

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Update

I tried to do the following:

MyObject = {
  properties       : this.propertiesDefault,
  resetProperties  : function resetProperties() { this.properties = [{}] },
  propertiesDefault: [{}]
};

but I get “TypeError: invalid 'in' operand MyObject.properties” and I am not sure that is the right way to proceed.

Answer 1

It seems to me that it would be impossible to avoid having your default / reset properties as a separate object to the one that will be modified.

I would recommend having a default value, and cloning it in your initialisation and reset function. Since you tagged your question with jQuery, I assume you are happy to clone the object with that:

MyObject = {
    defaultProperties : [{}],
    properties : jQuery.extend(true, {}, this.defaultProperties),
    resetProperties: function() { 
        this.properties = jQuery.extend(true, {}, this.defaultProperties);
    }
};

See this Stack Overflow question for more information on cloning objects:

What is the most efficient way to deep clone an object in JavaScript?

This is the documentation for jQuery.extend:

http://docs.jquery.com/Utilities/jQuery.extend