mixin.js

var GeneralMixins = {
  preventHref: function(e) {
    e.preventDefault();
  }
};

// ...
// note: the view is titled ShareLinks
// ...
  events: {
    'click .facebook-share' : 'postToFeed',
    'click a[href="#"]' : 'preventHref'
  }
// ...

_.extend(ShareLinks.prototype, GeneralMixins);