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JavaScript JavaScript Loops, Arrays and Objects Simplify Repetitive Tasks with Loops `do ... while` Loops

Joshua Swilling
Joshua Swilling
1,135 Points
Posted by Joshua Swilling
Joshua Swilling
1,135 Points

do-while loop

I am curious and want to ask, can any operator be used to test conditions within the " while( ____ )" half of the loop?

2 Answers

Juan Naputi
Juan Naputi
1,772 Points
Juan Naputi
Juan Naputi
1,772 Points

Yup! All of the conditional operators (===, !==, >, <, >=, <=) are valid inside of the "while()" half of the loop.

Andrew Baran
Andrew Baran
Courses Plus Student 5,139 Points
Andrew Baran
Andrew Baran
Courses Plus Student 5,139 Points

Can you tell me how come this doesn't work? while ( !== correctGuess)

and why this doesn't work either?

while ( guess ! correctGuess)

Thank you

Juan Naputi
Juan Naputi
1,772 Points
Juan Naputi
Juan Naputi
1,772 Points

For while ( !== correctGuess), you have to provide a value that you want to compare. Typical setup would be: while ([!] {variableToCheck} {comparisonOperator} {valueToCheckAgainst}). With this template, you are missing the {variableToCheck} part of your while-loop.

For the second one, while (guess ! correctGuess), you have to use one of the valid comparison operators (===, !==, ==, !=, >=, <=). If you don't have these, it is an invalid comparison. The only time you will be using an not [!] comparison on its own is if you are looking for a false boolean value: while ( !isTrue ).

I can expand the context if needed.

Hope that helps!

*** For the first answer, the [!] at the front means that it is optional and is used when you are checking for a false boolean value. Refer to the second answer for a reference.