PHP 8.4: round() - Invalid rounding modes throw \ValueError exceptions
The round() function rounds a float value to the nearest integer or a decimal value of a specified precision. It supports fine-tuning the rounding method with an additional parameter.
Prior to PHP 8.4, passing an invalid rounding mode parameter silently assumed the default PHP_ROUND_HALF_UP rounding mode. In PHP 8.4 and later, passing invalid rounding mode results in a \ValueError exception, and is no longer assumed as PHP_ROUND_HALF_UP.
round(num: 3.14, mode: 42); // Invalid $mode parameterValueError: round(): Argument #3 ($mode) must be a valid rounding mode (PHP_ROUND_*).Related Changes
Backward Compatibility Impact
Passing an invalid $mode parameter to the round() function results in a ValueError exception being thrown in PHP 8.4 and later. This is intended to correct the possibly unexpected behavior in previous PHP versions that assumed the default PHP_ROUND_HALF_UP rounding mode upon invalid values.
PHP code that do not pass a $mode parameter to the round function calls at all, or pass correct parameter values (PHP_ROUND_* constants) will not see any functionality changes. Any PHP applications that receive the exceptions can safely drop the additional parameter to mimic the existing behavior without causing the exception.
- round(num: 3.14, mode: 42);
+ round(num: 3.14);