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Hoessein Abd
Python Web Development Techdegree Graduate 19,107 PointsWhy does the 'Throw new error' function end the program?
function getRandomNumber( lower, upper ) {
if (isNaN(lower) || isNaN(upper) ) {
throw new Error('You can only enter numbers');
}
return Math.floor(Math.random() * (upper - lower + 1)) + lower;
}
document.write( getRandomNumber( 'nine', 24 ) );
document.write( getRandomNumber( 1, 100 ) );
document.write( getRandomNumber( 200, 'five hundred' ) );
document.write( getRandomNumber( 1000, 20000 ) );
document.write( getRandomNumber( 50, 100 ) );
This function will test if the arguments passed in are numbers. I completed and understood the challenge, but expected other results.
Here is my confusion: when you call the function for the first time it will throw an error. But why won't it continue to run the 2nd time the function is called? Why does the program stop after the first failed test?
2 Answers
Jennifer Mitchell
Full Stack JavaScript Techdegree Student 3,917 PointsThere is no catch block in your code, so the program terminates. the MDN documentation does explain catch blocks, but that doesn't apply here.
Olga DC
16,680 PointsAccording to the MDN documentation: The throw statement throws a user-defined exception. Execution of the current function will stop (the statements after throw won't be executed), and control will be passed to the first catch block in the call stack. If no catch block exists among caller functions, the program will terminate.
Hoessein Abd
Python Web Development Techdegree Graduate 19,107 Pointsthanks for your reply. do you know what: "control will be passed to the first catch block in the call stack." means?