ES2015 template string

[guinness]

function valueToUpper(strings, ...values) {
    // Set the values i.e. first and last name to upper-case
    values[0] = values[0].toUpperCase();
    values[1] = values[1].toUpperCase();

    // Re-create the template
    return `${strings[0]}${values[0]}${strings[1]}${values[1]}${strings[2]}`;
}

// Create first and last name variables
const firstName = 'Joe';
const lastName = 'Bloggs';

// Pass the template to a custom format function
const template = valueToUpper `Welcome ${firstName} ${lastName} to the site.`;

// Display the new template
console.log(template);

Template strings are such a huge game changer. No more awful concatenation, see http://www.typescriptlang.org/play/#src=function%20valueToUpper(strings%2C%20...values)%20%7B%0A%20%20%20%20%2F%2F%20Set%20the%20values%20i.e.%20first%20and%20last%20name%20to%20upper-case%0A%20%20%20%20values%5B0%5D%20%3D%20values%5B0%5D.toUpperCase()%3B%0A%20%20%20%20values%5B1%5D%20%3D%20values%5B1%5D.toUpperCase()%3B%0A%0A%20%20%20%20%2F%2F%20Re-create%20the%20template%0A%20%20%20%20return%20%60%24%7Bstrings%5B0%5D%7D%24%7Bvalues%5B0%5D%7D%24%7Bstrings%5B1%5D%7D%24%7Bvalues%5B1%5D%7D%24%7Bstrings%5B2%5D%7D%60%3B%0A%7D%0A%0A%2F%2F%20Create%20first%20and%20last%20name%20variables%0Aconst%20firstName%20%3D%20'Joe'%3B%0Aconst%20lastName%20%3D%20'Bloggs'%3B%0A%0A%2F%2F%20Pass%20the%20template%20to%20a%20custom%20format%20function%0Aconst%20template%20%3D%20valueToUpper%20%60Welcome%20%24%7BfirstName%7D%20%24%7BlastName%7D%20to%20the%20site.%60%3B%0A%0A%2F%2F%20Display%20the%20new%20template%0Aconsole.log(template)%3B (URL plugin didn't work) for how TypeScript transpiles this to ES5, yeah awful looking!

function valueToUpper(strings, ...values) {
    // Set the values i.e. first and last name to upper-case
    values[0] = values[0].toUpperCase();
    values[1] = values[1].toUpperCase();

    // Re-create the template
    return `${strings[0]}${values[0]}${strings[1]}${values[1]}${strings[2]}`;
}

// Create first and last name variables
const firstName = 'Joe';
const lastName = 'Bloggs';

// Pass the template to a custom format function
const template = valueToUpper `Welcome ${firstName} ${lastName} to the site.`;

// Display the new template
console.log(template);

Edited April 10, 2016 by guinness

[guinness]

Updated the example to adhere to the Airbnb styleguide