const isOpen = false;
const isClosed = !isOpen;
console.log(isClosed);isClosed receives true without manually repeating the value.
LESSON 17 OF 50
Invert a boolean value
Use ! to negate a condition.
STEP 1 · LEARN
How it works
The logical NOT operator converts its operand to boolean and reverses the result. Negating false produces true.
const isClosed = isOpen;Copying the value preserves false; it does not invert it.
STEP 2 · APPLY
Your exercise
Declare isClosed as the negation of isOpen and print the result.
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STEP 4 · CHECK
What needs to pass
0%not checked
- ○isOpen and isClosed are declared with const.
- ○isClosed uses !isOpen.
- ○The output is true.
Explain the solution logic
The ! operator calculates the opposite value, and the console confirms the resulting boolean.