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Errors · medium

36. Custom Error Hierarchies

Subclassing Error and domain exception modeling.

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Create domain-specific errors by subclassing `Error` and setting `this.name`. This enables granular `catch` and handling strategies.

js
class InsufficientFundsError extends Error {
  constructor(msg) {
    super(msg);
    this.name = "InsufficientFundsError";
  }
}

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  1. 1. How do you check for a custom error instance?

  2. 2. What should custom error constructors call first?

  3. 3. Why assign this.name in custom errors?

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