(PHP 5, PHP 7) Finds position of first occurrence of a needle within a haystack

(PHP 4 >= 4.0.2, PHP 5, PHP 7) Set a file that contains personal wordlist

(PHP 5 >= 5.3.0, PHP 7, PECL intl >= 1.0.0) Set the pattern used for the IntlDateFormatter

(PHP 5 >= 5.3.0, PHP 7, PECL intl >= 1.0.0) Get the error text from the last operation

(PHP 5 >= 5.3.0, PHP 7, PECL intl >= 1.0.0) Format a number

(PHP 5.5.0, PHP 7, PECL >= 3.0.0a1) Whether a certain date/time is in the weekend