assert Checks if assertion is &false; &reftitle.description; boolassert mixedassertion stringdescription assert will check the given assertion and take appropriate action if its result is &false;. If the assertion is given as a string it will be evaluated as PHP code by assert. The advantages of a string assertion are less overhead when assertion checking is off and messages containing the assertion expression when an assertion fails. This means that if you pass a boolean condition as assertion this condition will not show up as parameter to the assertion function which you may have defined with the assert_options function, the condition is converted to a string before calling that handler function, and the boolean &false; is converted as the empty string. Assertions should be used as a debugging feature only. You may use them for sanity-checks that test for conditions that should always be &true; and that indicate some programming errors if not or to check for the presence of certain features like extension functions or certain system limits and features. Assertions should not be used for normal runtime operations like input parameter checks. As a rule of thumb your code should always be able to work correctly if assertion checking is not activated. The behavior of assert may be configured by assert_options or by .ini-settings described in that functions manual page. The assert_options function and/or ASSERT_CALLBACK configuration directive allow a callback function to be set to handle failed assertions. assert callbacks are particularly useful for building automated test suites because they allow you to easily capture the code passed to the assertion, along with information on where the assertion was made. While this information can be captured via other methods, using assertions makes it much faster and easier! The callback function should accept three arguments. The first argument will contain the file the assertion failed in. The second argument will contain the line the assertion failed on and the third argument will contain the expression that failed (if any — literal values such as 1 or "two" will not be passed via this argument). Users of PHP 5.4.8 and later may also provide a fourth optional argument, which will contain the description given to assert, if it was set. &reftitle.parameters; assertion The assertion. description An optional description that will be included in the failure message if the assertion fails. &reftitle.returnvalues; &false; if the assertion is false, &true; otherwise. &reftitle.changelog; &Version; &Description; 5.4.8 The description parameter was added. The description is also now provided to a callback function in ASSERT_CALLBACK mode as the fourth argument. &reftitle.examples; Assertion Failed: File '$file'
Line '$line'
Code '$code'

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"; } // Set up the callback assert_options(ASSERT_CALLBACK, 'my_assert_handler'); // Make an assertion that should fail assert('mysql_query("")'); ?> ]]> ]]> &example.outputs; &reftitle.seealso; assert_options