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4.13.7 Boolean Expressions

A boolean expression is a combination of relational or matching expressions using the boolean operators and, or and not, and, eventually, parentheses to control nesting:

Expression Result
x and y True only if both x and y are true.
x or y True if any of x or y is true.
not x True if x is false.

table 4.1: Boolean Operators

Binary boolean expressions are computed using shortcut evaluation:

x and y

If x ⇒ false, the result is false and y is not evaluated.

x or y

If x ⇒ true, the result is true and y is not evaluated.

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