Mini Shell

<?php

// Globals.
global $acf_stores, $acf_instances;

// Initialize plaeholders.
$acf_stores    = array();
$acf_instances = array();

/**
 * acf_new_instance
 *
 * Creates a new instance of the given class and stores it in the instances data store.
 *
 * @date    9/1/19
 * @since   5.7.10
 *
 * @param   string $class The class name.
 * @return  object The instance.
 */
function acf_new_instance( $class = '' ) {
	global $acf_instances;
	return $acf_instances[ $class ] = new $class();
}

/**
 * acf_get_instance
 *
 * Returns an instance for the given class.
 *
 * @date    9/1/19
 * @since   5.7.10
 *
 * @param   string $class The class name.
 * @return  object The instance.
 */
function acf_get_instance( $class = '' ) {
	global $acf_instances;
	if ( ! isset( $acf_instances[ $class ] ) ) {
		$acf_instances[ $class ] = new $class();
	}
	return $acf_instances[ $class ];
}

/**
 * acf_register_store
 *
 * Registers a data store.
 *
 * @date    9/1/19
 * @since   5.7.10
 *
 * @param   string $name The store name.
 * @param   array  $data Array of data to start the store with.
 * @return  ACF_Data
 */
function acf_register_store( $name = '', $data = false ) {

	// Create store.
	$store = new ACF_Data( $data );

	// Register store.
	global $acf_stores;
	$acf_stores[ $name ] = $store;

	// Return store.
	return $store;
}

/**
 * acf_get_store
 *
 * Returns a data store.
 *
 * @date    9/1/19
 * @since   5.7.10
 *
 * @param   string $name The store name.
 * @return  ACF_Data
 */
function acf_get_store( $name = '' ) {
	global $acf_stores;
	return isset( $acf_stores[ $name ] ) ? $acf_stores[ $name ] : false;
}

/**
 * acf_switch_stores
 *
 * Triggered when switching between sites on a multisite installation.
 *
 * @date    13/2/19
 * @since   5.7.11
 *
 * @param   int                           $site_id New blog ID.
 * @param   int prev_blog_id Prev blog ID.
 * @return  void
 */
function acf_switch_stores( $site_id, $prev_site_id ) {

	// Loop over stores and call switch_site().
	global $acf_stores;
	foreach ( $acf_stores as $store ) {
		$store->switch_site( $site_id, $prev_site_id );
	}
}
add_action( 'switch_blog', 'acf_switch_stores', 10, 2 );

/**
 * acf_get_path
 *
 * Returns the plugin path to a specified file.
 *
 * @date    28/9/13
 * @since   5.0.0
 *
 * @param   string $filename The specified file.
 * @return  string
 */
function acf_get_path( $filename = '' ) {
	return ACF_PATH . ltrim( $filename, '/' );
}

/**
 * acf_get_url
 *
 * Returns the plugin url to a specified file.
 * This function also defines the ACF_URL constant.
 *
 * @date    12/12/17
 * @since   5.6.8
 *
 * @param   string $filename The specified file.
 * @return  string
 */
function acf_get_url( $filename = '' ) {
	if ( ! defined( 'ACF_URL' ) ) {
		define( 'ACF_URL', acf_get_setting( 'url' ) );
	}
	return ACF_URL . ltrim( $filename, '/' );
}

/*
 * acf_include
 *
 * Includes a file within the ACF plugin.
 *
 * @date    10/3/14
 * @since   5.0.0
 *
 * @param   string $filename The specified file.
 * @return  void
 */
function acf_include( $filename = '' ) {
	$file_path = acf_get_path( $filename );
	if ( file_exists( $file_path ) ) {
		include_once $file_path;
	}
}