Polymer now supports mixin:
var mixinObj = {
foo: function() {
/* ... */
}
};
var mixinObj2 = {
foo2: function() {
/* ... */
}
};
Polymer('my-component', Polymer.mixin({ // Platform.mixin for polymer version < 0.5
bar: function() {
/* ... */
this.foo(); // all the functions in mixinObjs are now accessible through 'this'
this.foo2();
}
}, mixinObj, mixObj2); // Platform.mixin accepts multiple mixin objects
More info here