5 Questions
Explain the difference between variables declared with var, let, and const in JavaScript.
Variables declared with var are function-scoped, meaning they are only visible within the function where they are declared. Variables declared with let have block scope, which means they are only visible within the block (enclosed by curly braces) where they are declared. Variables declared with const also have block scope and are used for constants, meaning once a value is assigned to a const variable, it cannot be reassigned.
What happens if you try to reassign a value to a const variable in JavaScript?
It would result in an error, as you cannot reassign a const variable once a value is assigned to it.
How are variables declared with var, let, and const scope in JavaScript?
Variables declared with var are function-scoped, while variables declared with let and const have block scope.
Explain the concept of block scope in JavaScript.
Block scope means that variables are only visible within the block (enclosed by curly braces) where they are declared. This applies to variables declared with let and const in JavaScript.
Provide an example of using a const variable in a JavaScript function.
function exampleConst() { const z = 30; console.log(z); // Outputs 30 }
Test your knowledge of JavaScript variable declaration and scope with this quiz. Learn the differences between var, let, and const and understand their impact on variable visibility within functions and blocks.
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