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Lodash _.once


The lodash _.once method creates a new function that can only be executed once. On subsequent calls, the previously returned result is returned instead. This is particularly useful when only one instance of a function's result is required. The method takes a function as its argument, and returns a new function that only executes the original function the first time it is called.

To use the _.once method, simply provide it with the function to be executed once, and assign the returned value to a new variable. When this new variable is executed, the original function will only be called once, and subsequent calls will return the previously returned result.

Here is an example usage of the _.once method:

const processPayment = _.once(() => {
  console.log('Processing Payment...');

processPayment(); // logs 'Processing Payment...'
processPayment(); // nothing happens

In this example, the processPayment function will only perform its action (logging 'Processing Payment...') the first time it is called. On any subsequent calls, the same logged output will be returned without actually executing the function.

Overall, the lodash _.once method can be incredibly helpful in scenarios where you need to execute a function only once, and then reuse its returned value multiple times. This can help optimize your application's performance and reduce the amount of unnecessary computation.