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assert_options

(PHP 4, PHP 5, PHP 7, PHP 8)

assert_optionsSet/get the various assert flags

Warning

This function has been DEPRECATED as of PHP 8.3.0. Relying on this function is highly discouraged.

Description

assert_options(int $option, mixed $value = ?): mixed

Set the various assert() control options or just query their current settings.

Note: The use of assert_options() is discouraged in favor of setting and getting the php.ini directives zend.assertions and assert.exception with ini_set() and ini_get(), respectively.

Parameters

option

Assert Options
Option INI Setting Default value Description
ASSERT_ACTIVE assert.active 1 enable assert() evaluation
ASSERT_EXCEPTION assert.exception 1 throws an AssertionError for each failed assertions
ASSERT_WARNING assert.warning 1 issue a PHP warning for each failed assertion
ASSERT_BAIL assert.bail 0 terminate execution on failed assertions
ASSERT_QUIET_EVAL assert.quiet_eval 0 disable error_reporting during assertion expression evaluation. Removed as of PHP 8.0.0.
ASSERT_CALLBACK assert.callback (null) Callback to call on failed assertions

value

An optional new value for the option.

The callback function set via ASSERT_CALLBACK or assert.callback should have the following signature:

assert_callback(
    string $file,
    int $line,
    ?string $assertion,
    string $description = ?
): void
file
The file where assert() has been called.
line
The line where assert() has been called.
assertion
Prior to PHP 8.0.0, the assertion which has been passed to assert(), but only when the assertion is given as a string. (If the assertion is a boolean condition, this parameter will be an empty string.) As of PHP 8.0.0, this parameter is always null.
description
The description that has been passed to assert().

Passing an empty string as value resets the assert callback.

Return Values

Returns the original setting of any option.

Errors/Exceptions

If option is not a valid option a ValueError is thrown.

Changelog

Version Description
8.3.0 assert_option() is now deprecated.
8.0.0 If option is not a valid option, a ValueError is now thrown. Previously false was returned.

Examples

Example #1 assert_options() example

<?php
// This is our function to handle
// assert failures
function assert_failure($file, $line, $assertion, $message)
{
echo
"The assertion $assertion in $file on line $line has failed: $message";
}

// This is our test function
function test_assert($parameter)
{
assert(is_bool($parameter));
}

// Set our assert options
assert_options(ASSERT_ACTIVE, true);
assert_options(ASSERT_BAIL, true);
assert_options(ASSERT_WARNING, false);
assert_options(ASSERT_CALLBACK, 'assert_failure');

// Make an assert that would fail
test_assert(1);

// This is never reached due to ASSERT_BAIL
// being true
echo 'Never reached';
?>

See Also

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User Contributed Notes 1 note

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4
Fr?d?ric Bouchery
21 years ago
Here is an exemple how to use the assertion callback function :

<?php
assert_options
( ASSERT_CALLBACK, 'assert_callback');

function
assert_callback( $script, $line, $message ) {
echo
'You have a design error in your script <b>', $script,'</b> : line <b>', $line,'</b> :<br />';
echo
'<b>', ereg_replace( '^.*//\*', '', $message ), '</b><br /><br />';
echo
'Open the source file and check it, because it\'s not a normal behaviour !';
exit;
}

$x = 3;
assert('is_integer( $x ) && ($x >= 0) && ($x <= 10); //* $x must be an integer value from 0 to 10' );
echo
"0 <= $x <= 10";
?>

assertion is usefull for "design by contract" methodology ...
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