Can someone teach me the use of object : function (args)

[padib]

Hi, I'm reading some code from the Thunderbird source, and I can't figure out what this syntax means:

Code: Select all

var messageHeaderSink = {

  (Snipped Code)

  handleAttachment:
    function(contentType, url, displayName, uri, isExt)     
    {
      (body)
    }

  (Snipped Code)


};

It's in the form name : function (args).
Is it a class method?