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orElseLazy()

orElseLazy<T>(fn, fallbackFn): T

Executes a function and returns its result, or executes a fallback function if an error occurs. The fallback function is only executed when needed (lazy evaluation).

Type Parameters​

T: T​

The return type.

Parameters​

fn: () => T​

The function to execute.

fallbackFn: () => T​

The function to execute if the first function throws an error.

Returns: T​

The result of the function or the result of the fallback function.

Since​

2.0.0

Example​

const result = orElseLazy(
  () => JSON.parse('invalid json'),
  () => ({ error: 'Invalid JSON', timestamp: Date.now() })
);
console.log(result); // { error: 'Invalid JSON', timestamp: 1234567890 }

const config = orElseLazy(
  () => localStorage.getItem('config'),
  () => getDefaultConfig() // Only called if localStorage fails
);