Arrow function Javascript-Why my code show error?

Question

const getUserChoice = ***(userInput)*** => {
userInput = userInput.toLowerCase();
if (userInput==='rock' || userInput ==='paper'|| userInput==='scissors') {
return userInput ;
} else {
return 'Error';
}
}

It working fine

const getUserChoice = **userInput** => {
userInput = userInput.toLowerCase();
if (userInput==='rock' || userInput ==='paper'|| userInput==='scissors') {
return userInput ;
} else {
return 'Error';
}
}

It shows error.

as far as I know, if a function has only one parameter it is not necessary to use parenthesis but in this code snippet, it seems like parenthesis is mandatory.can anyone explain why?

Answer 1

I just removed the asterisks around the function parameter name and the code just works. What error message did you get BTW?

Answer 2

the 1st part is working but the 2nd part didn't.it shows syntex error although the only difference is a parenthesis in the parameter.