wp-includes/class-wp-widget.php:253Register all widget instances of this widget class.
public function _register() { $settings = $this->get_settings(); $empty = true; // When $settings is an array-like object, get an intrinsic array for use with array_keys(). if ( $settings instanceof ArrayObject || $settings instanceof ArrayIterator ) { $settings = $settings->getArrayCopy(); } if ( is_array( $settings ) ) { foreach ( array_keys( $settings ) as $number ) { if ( is_numeric( $number ) ) { $this->_set( $number ); $this->_register_one( $number ); $empty = false; } } } if ( $empty ) { // If there are none, we register the widget's existence with a generic template. $this->_set( 1 ); $this->_register_one(); } }Introduced in 2.8.0. Unchanged from 6.7.7 through 7.1.0.
Signature, return type and hooks compared across 5 parsed releases.
src/wp-includes/class-wp-widget.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it.