What is a JavaScript function?
A JavaScript function is a block of code designed to perform a particular task.
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❌When does a Javascript function runs?
A JavaScript function is executed when "something" invokes it (calls it).
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❌How do we call a JavaScript function?
We call a JavaScript function by calling it’s named followed by the call signature.
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👉🏼Let's write a function that returns a string that says "Hello World".
We can declare this function in two ways:
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🤯ES5 declaration:
function helloWorld(){
return 'Hello World';
}
🤯ES6 declaration: ⠀⠀⠀⠀⠀
const helloWorld = () => {
return 'Hello World'l
}
👉🏼To invoke our function we will write the name/keyword of out function followed by its signature like this:
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helloWorld(); // Hello World
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Congratulations, you just wrote your first JavaScript function!! 🎉🎉
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💭What was the first language you wrote "Hello World" on?