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action is not described

customize_update_(type) action-hook . WP 3.4.0

Fires when the WP_Customize_Setting::update() method is called for settings not handled as theme_mods or options.

The dynamic portion of the hook name, $this->type, refers to the type of setting.

Usage

add_action( 'customize_update_(type)', 'action_function_name_1543', 10, 2 );
function action_function_name_1543( $value, $this ){
	// action...
}
$value(mixed)
Value of the setting.
$this(WP_Customize_Setting)
WP_Customize_Setting instance.

Where the hook is called

WP_Customize_Setting::update()
customize_update_(type)
wp-includes/class-wp-customize-setting.php 689
do_action( "customize_update_{$this->type}", $value, $this );

Where the hook is used (in WP core)

Does not used.