Function declarations vs Function expressions

Function declarations

• Start with function
• Is hoisted

function sum(a, b) {
    return a + b;
}

Function expressions

• Assigns a function to a variable
• Can only be used after it is defined
• Is not hoisted
• Can be used as IIFE
• Often used as a callback
• Doesn't need a function name (creates an anonymous function)

let sum = function(a, b) {
    return a + b;
}

// This is also a function expression
button.addEventListener('click', function(event) {
    console.log('button is clicked!')
})

[[20230203023145-statement-vs-declaration]]

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