@function can.Component.extend @parent can.Component.static
Extends the [can.Component] constructor function.
@signature can.Component.extend(proto)
Extends the [can.Component] constructor function with prototype properties and methods.
@param {{}} proto An object set as the prototype of the constructor function. You will typically provide the following values on the prototype object.
@option {can.Component.prototype.tag} tag Defines the tag on which instances of the component constructor function will be created.
@option {can.Component.prototype.events} [events] Defines events on dom elements or observable objects the component listens to.
@option {can.Component.prototype.helpers} [helpers] Specifies mustache helpers used to render the component's template.
@option {can.Component.prototype.viewModel} [viewModel] Specifies an object that is is used to render the component's template.
@option {can.Component.prototype.tempate} [template] Specifies the template rendered within the custom element.
@body
Note that inheriting from components works differently than other CanJS APIs. You can't call .extend on a particular component to create a "subclass" of that component.
Instead, components work more like HTML elements. To reuse functionality from a base component, build on top of it with parent components that wrap other components in their template and pass any needed viewModel properties via attributes.