Summary
let myFunction = function() {
}
myFunction();Details
Function expressions are another way of writing expressions. Instead of just writing the function and giving it a name like a function declaration, you save the function to a variable or constant.
To write a function expression, first write a variable or constant. The name you use will be what you use to call the function.
let myFunctionNext, write an equals sign, the word function, a pair of parentheses, and a pair of curly braces.
let myFunction = function() {
}Calling the function is the same as calling a function declaration: you write the name of the function along with a pair of parentheses. The difference here is you have to call the function after the function expression (in other words, function expressions are not hoisted).
let myFunction = function() {
}
// This call can't be placed above the function expression
myFunction();You can also have function expressions with one or more parameters.
let myFunction = function(param1, param2) {
}
myFunction(arg1, arg2);Demo
Exercises
Try the following statements in the console:
let myFunction = function() {
console.log('This is a function expression');
}
myFunction();