Prints compacted human-readable information about a variable. Follows nearly the same behavior as PHP's built-in function print_r with some improvements that reduce unnecessary indentation and lines.

compact_print_r.php

<?php

/**
* Prints compacted human-readable information about a variable.  Follows nearly
* the same behavior as PHP's built-in function print_r  with some improvements.
* Namely, it reduces the output indentation for nested arrays and object,
* removes lines with a single parenthesis (open or close), and returns string
* representating boolean ("true" versus "false") when expression is a scalar
* boolean.  Requires PHP 5.4 or greater due to shorthand array syntax.
*
* Note: This may alter strings within $var that contain spaces or single
* parenthesis, so the behavior isn't exactly true to the built-in print_r.
*
* @param mixed  $expression The expression to be printed.
* @param bool   $return     When TRUE return the information rather than print.
* @return mixed If given a scalar the value itself will be printed, otherwise
*               an output notation very similar to print_r is printed.  If the
*               return parameter is TRUE this string is returned, not printed.
* @author Bryon Elston <bryon@x10hosting.com>
*/

function compact_print_r($expression, $return = false) {
    $IND_FACTOR = 2;  # reduce indent by this factor (2 spaces become 1)
    
    # if expression is scalar (int, bool, etc) don't bother cleaning up
    if (is_scalar($expression)) {
        # return string "true" or "false" if expression is boolean
        if (is_bool($expression)) {
            $data = ($expression === true) ? 'true' : 'false';
            if ($return !== false)
                return $data;
            print $data;
            return;
        }
        # otherwise use the original print_r for this scalar value  
        return print_r($expression, $return);
    }
    
    # expression is an array or object, so we'll do the compacting on it
    $data = explode(PHP_EOL, print_r($expression, true));
    $prior_indent = 0; 
    $compacted = array_map(function($line) use ($prior_indent, $IND_FACTOR) {
        $t_line = trim($line);
        if ($t_line == '(' || $t_line == ')')
            return false;
        
        # count leading spaces
        $s_lead = strlen($line) - strlen(ltrim($line, ' '));
        $our_indent = 0;
        if ($s_lead > 0) {
            # reduce leading indent by factor of 2
            $line = str_replace(str_repeat(' ', $IND_FACTOR), ' ', $line);
            $our_indent = substr_count(
                $line, ' ', 0, $s_lead / $IND_FACTOR);
        }
        
        # less indent than prior line indicates new section, insert NL
        if ($our_indent < $prior_indent)
            $line = PHP_EOL . $line;
        
        $prior_indent = $our_indent;
        return $line;
    }, $data);
    
    # join lines back into a single string, keeping empty
    $compacted = implode(PHP_EOL, array_filter($compacted, function ($line) {
        return $line !== false;
    }));
    
    # return to caller if requested, match print_r default behavior
    if ($return !== false)
        return $compacted;
    
    print $compacted;
} 

# example usage:

$facts = [
    'giraffes' => ['are awesome', 'like bananas'],
    'cat'      => ['do not like bananas', 'like cats']
];

compact_print_r($facts);

// output is as follows:
// 
// Array
//   [giraffes] => Array
//       [0] => are awesome
//       [1] => like bananas
// 
//   [cat] => Array
//       [0] => do not like bananas
//       [1] => like cats