Deffered and Method chaining

¿Qué es un Deferred?
Permite encadenar distintas acciones (callbacks) y disparar cierta funcionalidad (otros callbacks) dependiendo de su estado.
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Method chaining, also known as named parameter idiom, is a common syntax for invoking multiple method calls in object-oriented programming languages. Each method returns an object, allowing the calls to be chained together in a single statement without requiring variables to store the intermediate results.
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