The assert() statement is a convenient mechanism for incorporating diagnostic tests in code. Expressions used with the standard assert statement should must avoid side-effects. Typically, the behavior of the assert statement depends on the status of a runtime property. When enabled, the assert statement is designed to evaluate its expression argument and throw an AssertionError if the result of the expression is false. When disabled, assert is defined to be a no-operation. Consequently, any side-effects resulting from evaluation of the expression in the assertion are lost when assertions are disabled.
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