Sarathlal N

Write custom data to WordPress default debug.log file

The debugging WordPress code is so simple and WordPress have a nice debug systems to simplify the process as well as standardize code across the core, plugins and themes.

During theme & plugin development, I feel that the debug.log file was the most useful tool. It help me to sort out error in easier manner.

additionally, often I feel that I have to confirm the values of my objects, variables etc in my code during development. The echo & var_dump() are too useful. But in few situations, they are not enough.

Below you can find a handy function that help us to write our custom data in the WordPress debug.log file. Put the below code snippet in your theme’s functions.php file or your custom plugin file.

if (!function_exists('write_log')) {
	function write_log ( $log )  {
		if ( true === WP_DEBUG ) {
			if ( is_array( $log ) || is_object( $log ) ) {
				error_log( print_r( $log, true ) );
			} else {
				error_log( $log );

Then call the function with our variable in our code like below one.


Check your debug.log file and if there is value in your variable, you can see that one.

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