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10 Modules
Which of the following statements about 'var', 'let', and 'const' are correct?
Variables declared with 'var' are function-scoped.
Variables declared with 'let' are block-scoped.
Variables declared with 'const' can be reassigned.
Variables declared with 'const' must be initialized at the time of declaration.
What will be the output of the following code?
var x = 10;
if (true) {
var x = 20;
}
console.log(x);
10
20
ReferenceError
undefined
What will be the output of the following code?
let a = 1;
if (true) {
let a = 2;
}
console.log(a);
1
2
ReferenceError
undefined
Which of the following are true regarding hoisting in JavaScript?
'var' declarations are hoisted to the top of their function scope.
'let' and 'const' declarations are hoisted but not initialized.
Variables declared with 'let' can be accessed before their declaration.
Functions declared with 'var' can be invoked before their declaration.
What will be the output of the following code?
const obj = { prop: 1 };
obj.prop = 2;
console.log(obj.prop);
1
2
ReferenceError
TypeError
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10 Modules