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Michael Braun
6,753 PointsWhy - correctGuess = false; wouldn't while(! correctGuess); make the the condition true from the beginning?
As described in the title, I can't wrap my head around the logic in this example. If
correctGuess = false
do { } while ( ! correctGuess);
Can somebody help me understand the logic behind this? If the ! operator turns the boolean value around, wouldn't ( ! correctGuess) be "true" from the start since it's set to "false"?
3 Answers
Steven Parker
229,732 PointsYou're right that "! correctGuess" would be true, which means the loop would keep repeating.
When the guess is right, then "! correctGuess" becomes false and the loop ends.
Michael Braun
6,753 PointsI think I'm starting to understand.
Please let me know if I'm understanding this correctly. So basically "while" is not comparing the statement in the while(condition) with "var correctGuess." The driving factor behind the execution of the loop is the fact that the while loop is waiting for the "false" boolean to exit. Since ! correctGuess evaluates to "true" once correctGuess is switched to true, the opposite will be applied in while (! correctGuess). Which evaluates to while(false) so the loop is exited. No comparison with any value here, just true or false essentially?
Is my thought process correct here?
Steven Parker
229,732 PointsYes, the boolean is tested directly without a comparison. But you made one error, here's a corrected version:
! correctGuess evaluates to "false" once correctGuess is switched to true
Michael Braun
6,753 PointsAwesome. Thank you for your help Steve!