What is the output of const x = 10; x = 20;?
A). 20
B). 10
C). Error
D). undefined
What does the ... operator do when used in a function parameter?
A). It spreads an array
B). It restates the parameters
C). It indicates a default parameter
D). It represents the rest of the arguments
What does the for...of loop iterate over?
A). Object properties
B). Object values
C). Array indices
D). Iterable objects
How do you declare a constant variable in ES6?
A). const
B). let
C). var
D). function
How do you define a default parameter in a function?
A). function(a, b = 2) {}
B). function(a, b: 2) {}
C). function(a, b = [2]) {}
D). function(a, b := 2) {}
How do you interpolate variables in a string using template literals?
A). Hello, + name + '!'
B). Hello, ${name}!
C). 'Hello, ' + name + '!'
D). Both A and B
What is the syntax for an arrow function in ES6?
A). function(a, b) { return a + b; }
B). (a, b) => { return a + b; }
C). (a, b) => a + b
D). Both B and C
What is the result of [...['a', 'b', 'c']]?
A). ['a', 'b', 'c']
B). [['a', 'b', 'c']]
C). ['abc']
D). Error
What is the output of [...'hello']?
A). ['hello']
B). ['h', 'e', 'l', 'l', 'o']
C). [104, 101, 108, 108, 111]
D). ['h', 'e', 'll', 'o']
What does Promise.resolve(5).then(console.log) print?
A). 5
B). undefined
C). null
D). Error