/ elang / scalars

Scalar Type: boolean

E's booleans are as you'd expect. There are only two boolean values, known as "true" and "false". Here are the applicable operators in precedence order.

Logical Or (don't-care-associative)

false || true

Evaluates left to right until it finds a true condition. If any are true, it returns true and stops evaluating. If all return false, then all are evaluated and the result is false.

Logical And (don't-care-associative)

false && true

Evaluates left to right until it finds a false condition. If any are false, it returns false and stops evaluating. If all return true, then all are evaluated and the result is true.

Boolean Comparisons (non-associative)

false == true

__equalizer.sameEver(false, true)

false != true

__equalizer.sameEver(false, true).not()

false & true

false.and(true)

false | true

false.or(true)

false ^ true

false.xor(true)

Whereas "&&" and "||" are flow control operators as well as logical operators, "&","|",and "^" are normal operators that always evaluate both their operands.

Unary Expressions (left associative)

! false

false.not()

true

As you'd expect.

Additional boolean Messages

In addition to the messages corresponding to the above operators, booleans respond to the pick(trueChoice, falseChoice) message.

? pragma.syntax("0.8")

? true.pick(3, 5)
# value: 3

? false.pick(3, 5)
# value: 5

In response to the pick message, true will return the trueChoice, and false will return the falseChoice.