gistfile1.js

var MyComponent = Factory({
  willMount: function(element, context) {
    console.log('component mounted', element.tagName);
  };

  willUnmount: function(element, context) {
    console.log('component unmount', element.tagName);
  };

  view: function() {
    return m('.component', 'hello');
  }
});

// would be transformed to:
var MyComponent = {
  controller: function() {
    this.willMount = function(element, context) {
      console.log('component mounted', element.tagName);
    };

    this.willUnmount = function(element, context) {
      console.log('component unmount', element.tagName);
    };
  },

  view: function(ctrl) {
    return m('.component', {
      config: function(element, isInitialised, context) {
        if (!isInitialised && ctrl.willMount) ctrl.willMount(element, context);

        if (ctrl.willUnmount) {
          context.onunload = function() {
            ctrl.willUnmount(element, context);
          }
        }
      }
    }, 'hello');
  }
}