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

The _.foldl() function from the Underscore library allows you to reduce an array to a single value using a provided function. The syntax for using _.foldl() is as follows:

index.tsx
_.foldl(list, iteratee, [memo], [context])
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• list is the input array to be reduced.
• iteratee is a function that is applied to each element of the array. This function should take two arguments: the current value and the accumulated result, and return a single value.
• memo is an optional initial value for the accumulated result.
• context is the optional this binding for the iteratee function.

Here's an example of how to use _.foldl():

index.tsx
const _ = require('underscore');

const numbers = [1, 2, 3, 4, 5];
const sum = _.foldl(numbers, function (memo, num) {
  return memo + num;
}, 0);

console.log(sum); // output: 15
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In this example, we're using _.foldl() to sum up an array of numbers. The iteratee function takes two arguments: memo, which is the current sum, and num, which is the current element of the array. The function returns the sum of memo and num, which becomes the new value of memo on the next iteration.

The initial value of memo is set to 0 using the optional memo argument.

Note that require('underscore') is used to import the Underscore library in Node.js. If you're using Underscore in a browser environment, you may need to include it as a script tag instead.