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

The partial function from Underscore allows you to create a new function that has some of the arguments of the original function pre-filled with specific values. This can be very useful when you want to reuse a function with some of the arguments already defined.

Here's an example of how to use partial:

index.tsx
// First, include Underscore in your project
var _ = require('underscore');

// Define a function that takes two arguments
function multiply(a, b) {
  return a * b;
}

// Use partial to create a new function that multiplies by 5
var multiplyBy5 = _.partial(multiply, 5);

// Call the new function with a single argument
var result = multiplyBy5(10); // Returns 50
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In this example, we define a function multiply that takes two arguments. Then, we use _.partial to create a new function called multiplyBy5 that takes a single argument and always multiplies it by 5. We pass multiply as the first argument to _.partial and 5 as the second argument, which tells partial to pre-fill the first argument of multiply with 5. Finally, we call multiplyBy5 with the argument 10 and get the expected result of 50.

You can use _.partial with any function that has more than one argument, and you can pre-fill as many or as few arguments as you need.