Return a comma-separated string of functions that have been called to get to the current point in code.

Signature

wp_debug_backtrace_summary( $ignore_class = null, $skip_frames = 0, $pretty = true )
ignore_class
 (string) Optional. A class to ignore all function calls within - useful when you want to just give info about the callee. Default null.
Default: null
skip_frames
 (int) Optional. A number of stack frames to skip - useful for unwinding back to the source of the issue. Default 0.
Default: 0
pretty
 (boolean) Optional. Whether or not you want a comma separated string or raw array returned. Default true.
Default: true

Return

(string|array) Either a string containing a reversed comma separated trace or an array of individual calls.

Source

function wp_debug_backtrace_summary( $ignore_class = null, $skip_frames = 0, $pretty = true ) {
	if ( version_compare( PHP_VERSION, '5.2.5', '>=' ) )
		$trace = debug_backtrace( false );
	else
		$trace = debug_backtrace();

	$caller = array();
	$check_class = ! is_null( $ignore_class );
	$skip_frames++; // skip this function

	foreach ( $trace as $call ) {
		if ( $skip_frames > 0 ) {
			$skip_frames--;
		} elseif ( isset( $call['class'] ) ) {
			if ( $check_class && $ignore_class == $call['class'] )
				continue; // Filter out calls

			$caller[] = "{$call['class']}{$call['type']}{$call['function']}";
		} else {
			if ( in_array( $call['function'], array( 'do_action', 'apply_filters' ) ) ) {
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