WordPress at a glance
function is not described

POMO_Reader::substr() public WP 1.0

{} It's a method of the class: POMO_Reader{}

No Hooks.

Return

String. Null. Nothing.

Usage

$POMO_Reader = new POMO_Reader();
$POMO_Reader->substr( $string, $start, $length );
$string(string) (required)
-
$start(int) (required)
-
$length(int) (required)
-

Code of POMO_Reader::substr() WP 5.7.1

<?php
function substr( $string, $start, $length ) {
	if ( $this->is_overloaded ) {
		return mb_substr( $string, $start, $length, 'ascii' );
	} else {
		return substr( $string, $start, $length );
	}
}