How Can I Handle Asynchronous Operations Within a JavaScript Constructor?

Constructor Invocation of Asynchronous Code

Within a constructor function, it seems desirable to utilize asynchronous code using async/await for convenience. However, invoking the await operator within a constructor is prohibited in JavaScript due to its incompatible return types.

In essence, async functions return promises, representing an operation that will complete in the future. Conversely, constructors return the instantiated object they create. This dichotomy poses a conflict.

Solutions

To overcome this limitation, two design patterns emerge:

1. Initialization Function (init):

   • Introduce an init() function that serves like jQuery's .ready().
   • The constructed object is only usable within its own init function.

2. Builder Pattern:

   • An alternative to dependency injection as seen in Java.
   • The builder does not return the object but a promise that resolves to the object.

Note on Static Invocation

When invoking functions within static methods, remember:

• this refers to the instantiated object, not the class.
• Static functions are bound directly to the class and cannot access object properties by default.

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