Understanding Void and Never Types in TypeScript

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What is the return type of the function sayHi() in the given example?

void

undefined (correct)

string

never

Why does the type assertion 'speech: never' result in a compile-time error?

because never is not a valid type in TypeScript

because void is not assignable to never (correct)

because the type assertion is not necessary

because the function sayHi() does not return a value

What is the purpose of the interface Employee in the given example?

to define a type for an object (correct)

to define a property

to define a function

to define a variable

What is the result of the expression 'x > y' in the given example?

false Signup and view all the answers

What is the purpose of the ternary operator in the given example?

to check for a boolean condition and execute one of two statements Signup and view all the answers

What is the value of the variable empl after the code snippet is executed?

{ name: 'Kallis', code: 2015 } Signup and view all the answers

What is the scope of the variable 'z' in the given code snippet?

Local to the if block Signup and view all the answers

What is the purpose of the '?' symbol in TypeScript function parameters?

To indicate that the parameter is optional Signup and view all the answers

What is the advantage of using let over var in terms of variable declaration?

It prevents variable re-declaration Signup and view all the answers

What will happen if you declare a variable with the same name as a function argument in a function using let?

It will give a compiler error Signup and view all the answers

What is the difference between JavaScript and TypeScript in terms of function argument passing?

JavaScript expects fewer arguments than defined in the function signature, whereas TypeScript expects the exact number Signup and view all the answers

What is the difference between let and const variable declarations?

let variables cannot be re-declared Signup and view all the answers

What is the characteristic of an anonymous function in TypeScript?

It is defined as an expression and stored in a variable Signup and view all the answers

What is the purpose of the function signature in TypeScript?

To specify the function return type and parameter types Signup and view all the answers

What is the purpose of template strings in TypeScript?

To embed expressions into strings Signup and view all the answers

What happens in TypeScript when a function is called with fewer arguments than defined in the function signature?

The compiler throws an error Signup and view all the answers

What is the error that will be thrown if you try to assign a value to a const variable?

Cannot assign to 'num' because it is a constant or read-only property Signup and view all the answers

What is the benefit of using optional parameters in TypeScript?

It allows for more flexibility in function calls Signup and view all the answers

Understanding Void and Never Types in TypeScript

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