The behaviour of these functions is affected by settings in php.ini.
|intl.use_exceptions||0||PHP_INI_ALL||Available since PHP 5.5 and PECL 3.0.0a1|
Here's a short explanation of the configuration directives.
The locale that will be used in intl functions when none is specified (either by omitting the corresponding argument or by passing NULL). These are ICU locales, not system locales. The built-in ICU locales and their data can be explored at » http://demo.icu-project.org/icu-bin/locexp.
The default value is empty, which forces the usage of ICU's default locale. Once set, the ini setting cannot be reset to this default value. It is not recommended that this default be relied on, as its effective value depends on the server's environment.
The level of the error messages generated when an error occurs in ICU functions. This is a PHP error level, such as
E_WARNING. It can be set to 0 in order to inhibit the messages. This does not affect the return values indicating error or the values returned by intl_get_error_code() or by the class specific methods for retrieving error codes and messages. Choosing E_ERROR will terminate the script whenever an error condition is found on intl classes.
The default value is 0.
If set to true, an exception will be raised whenever an error occurs in an intl function. The exception will be of type IntlException. This is possibly in addition to the error message generated due to intl.error_level.
The default value is