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php7Expect backward-compatible enhancements to the old assert() function. Expectations allow zero-cost assertions in production code and provide the ability to throw custom exceptions when assertions fail. assert() is not a language construct where the first argument is a comparison of an expression string or boolean for testing.
Configuration directive assert()
| Default value | Possible values | |
| 1 | 1 \- Generate and execute code (development mode ) 0 \- Generate code, but skip it at runtime -1 \- Do not generate code (production mode) | |
| 0 | 1 \- Throws the exception object provided when the assertion fails, or throws a new AssertionError object if no exception is provided. . 0 \- Use or generate a Throwable as above, but only generate a warning based on that object instead of throwing it (compatible with PHP 5 behavior) |
PHP 5, it must be a string to be evaluated or a boolean value to be tested. In PHP 7, this can also be any expression that returns a value that will be executed and the result used to indicate whether the assertion succeeded or failed.
PHP 7, the second parameter can be a Throwable object instead of a descriptive string, in which case This is the object that will be thrown if the assertion fails and the assert.exception configuration directive is enabled.
FALSE, otherwise it returns TRUE .
<?php
ini_set('assert.exception', 1);
class CustomError extends AssertionError {}
assert(false, new CustomError('Custom Error Message!'));
?>It produces the following browser output:Fatal error: Uncaught CustomError: Custom Error Message! in...Recommended:
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