AngularJS AngularJS bindings options (`=`, `@`, `&` etc.) = two-way binding.
Example
Passing in a value by reference, you want to share the value between both scopes and manipulate them from both scopes. You should not use {{...}} for interpolation.
<two-way text="'Simple text.'" <!-- 'Simple text.' -->
simple-value="123" <!-- 123 Note, is actually a number now. -->
interpolated-value="parentScopeValue" <!-- Some value from parent scope. You may change it in one scope and have updated value in another. -->
object-item="objectItem" <!-- Some object from parent scope. You may change object properties in one scope and have updated properties in another. -->
<!-- Unexpected usage. -->
interpolated-function-value="parentScopeFunction()" <!-- Will raise an error. -->
function-item="incrementInterpolated"> <!-- Pass the function by reference and you may use it in child scope. -->
</two-way>
Passing function by reference is a bad idea: to allow scope to change the definition of a function, and two unnecessary watcher will be created, you need to minimize watchers count.
