how to use the compose function from the underscore library in javascript

The _.compose() method from the Underscore library allows you to chain multiple functions together and create a new function that applies each of them one after the other. Here's an example usage:

index.tsx
// Define some functions to compose
function addTwo(x) {
  return x + 2;
}

function square(x) {
  return x * x;
}

function negate(x) {
  return -x;
}

// Compose the functions together
var composedFunc = _.compose(negate, square, addTwo);

// Call the composed function
console.log(composedFunc(5)); // Outputs: -49
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In the above example, we first define three functions addTwo(), square(), and negate() that we want to compose together. Then we create a new function composedFunc using _.compose(), passing in the three functions in order (right-to-left) that we want to apply. Finally, we call composedFunc with a value of 5, which applies each of the three composed functions to the value in turn, resulting in -49.

The _.compose() function is a higher-order function, which means it takes one or more functions as arguments and returns a new function. This makes it suitable for use in functional programming, where functions are treated as first-class objects and can be passed around and composed together in various ways.