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filter is not described

customize_validate_(id) filter-hook . WP 4.6.0

Validates a Customize setting value.

Plugins should amend the $validity object via its WP_Error::add() method.

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

Usage

add_filter( 'customize_validate_(id)', 'filter_function_name_5293', 10, 3 );
function filter_function_name_5293( $validity, $value, $this ){
	// filter...

	return $validity;
}
$validity(WP_Error)
Filtered from true to WP_Error when invalid.
$value(mixed)
Value of the setting.
$this(WP_Customize_Setting)
WP_Customize_Setting instance.

Where the hook is called

WP_Customize_Setting::validate()
customize_validate_(id)
wp-includes/class-wp-customize-setting.php 597
$validity = apply_filters( "customize_validate_{$this->id}", $validity, $value, $this );

Where the hook is used (in WP core)

wp-includes/class-wp-customize-setting.php 185
add_filter( "customize_validate_{$this->id}", $this->validate_callback, 10, 3 );