Logical NOT

Part of the Fundamentals section of Coddy's Dart journey — lesson 25 of 94.

The logical NOT operator (!) reverses boolean values, turning true to false and vice versa.

void main() {
  bool isRaining = true;
  bool isNotRaining = !isRaining;
  
  print('Is it raining? $isRaining');
  print('Is it not raining? $isNotRaining');
}

Output:

Is it raining? true
Is it not raining? false

It's useful for checking negative conditions and can combine with other logical operators.

Challenge

Easy

Create a program that demonstrates the Logical NOT (!) operator in Dart:

Declare a boolean variable isRaining and set it to true
Declare a boolean variable hasUmbrella and set it to false
Create a new boolean variable willGetWet that is true if it's raining AND the person does NOT have an umbrella (use the ! operator)
Create another boolean variable canGoOutside that is true if it's NOT raining OR the person has an umbrella (use the ! operator)
Print all four variables with the EXACT following format:

Is it raining? true
Do you have an umbrella? false
Will you get wet? true
Can you go outside? false

Your output must match this exact format.

Cheat sheet

The logical NOT operator (!) reverses boolean values, turning true to false and vice versa.

bool isRaining = true;
bool isNotRaining = !isRaining;

print('Is it raining? $isRaining');        // true
print('Is it not raining? $isNotRaining'); // false

The NOT operator is useful for checking negative conditions and can combine with other logical operators.

Try it yourself

void main() {
  // Declare your boolean variables here
  bool isRaining = ?;
  bool hasUmbrella = ?;
  
  // Calculate willGetWet using logical NOT with AND
  bool willGetWet = ?;
  
  // Calculate canGoOutside using logical NOT with OR
  bool canGoOutside = ?;
  
  // Print the variables with labels
  print("Is it raining? $isRaining");
  print("Do you have an umbrella? $hasUmbrella");
  print("Will you get wet? $willGetWet");
  print("Can you go outside? $canGoOutside");
}