{properties} = object syntax

[Mnus]

Cu.import("resource://gre/modules/NewTabUtils.jsm");

var {
  links: gLinks,
  allPages: gAllPages,
  linkChecker: gLinkChecker,
  pinnedLinks: gPinnedLinks,
  blockedLinks: gBlockedLinks,
  gridPrefs: gGridPrefs
} = NewTabUtils;

and the scipt of NewTabUtils.jsm is

/**
 * Singleton that provides the public API of this JSM.
 */
this.NewTabUtils = {
 a_Property_is_here: false,
 Some_Method_A: function Some_Method_A() {
}
 Some_Method_B: function Some_Method_A() {
}
 And_so_on: function And_so_on() {
}
  links: Links,
  allPages: AllPages,
  linkChecker: LinkChecker,
  pinnedLinks: PinnedLinks,
  blockedLinks: BlockedLinks,
  gridPrefs: GridPrefs,
  placesProvider: PlacesProvider,
  activityStreamLinks: ActivityStreamLinks,
  activityStreamProvider: ActivityStreamProvider
};

What does the part "var{properties}=NewTabUtils;"  mean? I understand if that's "NewTabUtils={properties};"

And another minor question is about the second script, in the Class-like JS methods, properties are asigned at bottom of the script, also bottom of the file. I guess that's because it is easy to read, but not sure the reason.

Would somebody know these questions?

thanks.

[justsomeguy]

That syntax doesn't look valid.  What is that for, does that get run through an interpreter or something to produce regular Javascript?  What is .jsm?