how to use the unary function from lodash in javascript

To use the unary function from lodash in JavaScript, we first need to install the lodash library. This can be done using npm:

index.tsx
npm install lodash
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After installing lodash, we can use the unary function by importing it into our JavaScript file using the require function:

index.tsx
const _ = require('lodash');
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The unary function takes a function as its only argument, and returns a new function that accepts only one argument. This can be useful when we want to pass a function that expects multiple arguments to a function that expects only one argument. Here's an example:

index.tsx
const multiply = (a, b) => a * b;
const unaryMultiply = _.unary(multiply);

console.log(multiply(2, 3)); // Output: 6
console.log(unaryMultiply(2, 3)); // Output: 2
console.log(_.map(['1', '2', '3'], unaryMultiply)); // Output: [1, 2, 3]
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In the example above, multiply is a function that expects two arguments, and unaryMultiply is a new function created using the unary function from lodash. The unaryMultiply function expects only one argument, and when called with two arguments, it uses only the first argument and ignores the rest.

Finally, we pass the unaryMultiply function to the map function from lodash, which expects a function that takes only one argument. The resulting array contains the values of the original array after being passed through the unary function.