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filter is not described

deprecated_function_trigger_error filter-hook . WP 2.5.0

Filters whether to trigger an error for deprecated functions.

Usage

add_filter( 'deprecated_function_trigger_error', 'filter_function_name_3395' );
function filter_function_name_3395( $trigger ){
	// filter...

	return $trigger;
}
$trigger(true/false)
Whether to trigger the error for deprecated functions.
Default: true

Where the hook is called

_deprecated_function()
deprecated_function_trigger_error
wp-includes/functions.php 3892
if ( WP_DEBUG && apply_filters( 'deprecated_function_trigger_error', true ) ) {

Where the hook is used (in WP core)

wp-includes/rest-api.php 161
add_filter( 'deprecated_function_trigger_error', '__return_false' );