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JavaScript JavaScript Functions Arrow Functions Testing for Number Arguments

Cody Norman
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Cody Norman
Full Stack JavaScript Techdegree Student 3,421 Points

Number arguments not working quite right

When I input the following into the JavaScript console I get my custom message of "You need to enter a numerical value!" and nothing else, however, if I add in 'lower = 1' the script runs exactly as it should. In the video Guil shows that lower value being blank and the script running just fine. Why is mine different, I actually changed my code from an arrow function to match the video EXACTLY hoping it would work.

function inputNum(lower, upper = 1000 ) { if ( isNaN(lower) || isNaN(upper) ) { throw Error('You need to enter a numerical value!'); } return Math.floor(Math.random() * (upper - lower + 1)) + lower; }

// Call the function and pass it different values

console.log( ${inputNum()} is a random number between 1 and 50 ); console.log(inputNum(75, 600) ); console.log(inputNum(30, 500) );

1 Answer

Steven Parker
Steven Parker
231,184 Points

In the video, the function is named "getRandomNumber", and he passes the value "10" to it to satisfy the "lower" argument.

Here, you are not passing any argument so the "lower" is not a number unless you define a default value.