2 simple functions we use at Human Made for debugging.

HM Debugging Functions

/**
 * Intelligently replacement for print_r & var_dump.
 *
 * @param mixed $code
 * @param bool $output. (default: true)
 * @return $code
 */
function hm( $code, $output = true ) {

    if ( $output ) : ?>

		<style>
			.hm_debug { word-wrap: break-word; white-space: pre; text-align: left; position: relative; background-color: rgba(0, 0, 0, 0.8); font-size: 11px; color: #a1a1a1; margin: 10px; padding: 10px; margin: 0 auto; width: 80%; overflow: auto;  -moz-border-radius: 5px; -webkit-border-radius: 5px; text-shadow: none; }
		</style>

		<br />

		<pre class="hm_debug">

	<?php endif;

	// var_dump everything except arrays and objects
	if ( ! is_array( $code ) && ! is_object( $code ) ) :

		if ( $output )
			var_dump( $code );

		else
			var_export( $code, true );

	else :

		if ( $output )
			print_r( $code );

		else
			print_r( $code, true );
	endif;

	if ( $output )
		echo '</pre><br />';

	return $code;

}

/**
 * Intelligently error_log the passed var.
 *
 * @param mixed $code
 */
function hm_log( $code ) {

	// var_dump everything except arrays and objects
	if ( ! is_array( $code ) && ! is_object( $code ) ) :
			error_log( var_export( $code, true ) );

	else :

			error_log( print_r( $code, true ) );
	endif;

	return $code;
}