Template literals in ES6 (EcmaScript) allows us to embed expressions to our string literals. We can use multi-line strings and string interpolation features with them.
Template literals are enclosed by the back-tick (` `) instead of double or single quotes.
var message = `single line string`; console.log(message); // single line string
We can include place holders for string substitution using ${ } syntax
var expression = "place holder"; // string substitution
console.log(`this is a text with ${expression} in a line`);
// this is a text with place holder in a line
We can directly use expression interpolation to embed inline math
var a = 5;
var b = 5;
console.log(`the addition of a+b = ${a+b}`);
// the addition of a+b = 10
We can also call functions and use member functions in strings
function sample() { return "text from sample method"; }
console.log(`yes! ${sample()} and i am in uppercase`.toUpperCase());
// YES! TEXT FROM SAMPLE METHOD AND I AM IN UPPERCASE
The above code retrieves data from sample() method and converts it to uppercase in run-time.
Multiline Strings
We can achieve multi line strings, previously we used to insert new line character in our string
console.log(`First line Second line`); // First line // Second line
Raw strings
The special raw property, available on the first function argument of tagged template literals, allows you to access the raw strings as they were entered.
String.raw`Hi \n ${2+3}!`;
// "Hi \n 5!"
Tagged template literals
A more advanced form of template literals are tagged template literals. With them we able to modify the output of template literals using a function. The first argument contains an array of string literals. The second, and each argument after the first one, are the values of the processed substitution expressions. We can use any name to our function.
var a = 1;
var b = 2;
function tag(strings, ...values) {
console.log(strings[0]); // "One "
console.log(strings[1]); // " Two"
console.log(strings[2]); // " Three"
console.log(values[0]); // 1
console.log(values[1]); // 2
}
tag`One ${ a } Two ${ b } Three`;
// One
// Two
// Three
// 1
// 2
Happy exploring EcmaScript 🙂
Efficient User 