Convert the output string of print_r to array again.

print_r_reverse.php

<?php
// original author: https://www.php.net/manual/en/function.print-r.php#93529
// another dev said it was fixed for null values, but I don't encountered errors with null values for Matt's: https://www.php.net/manual/en/function.print-r.php#121259

// Matt
function print_r_reverse($in) {
    $lines = explode("\n", trim($in));
    if (trim($lines[0]) != 'Array') {
        // bottomed out to something that isn't an array
        return $in;
    } else {
        // this is an array, lets parse it
        if (preg_match("/(\s{5,})\(/", $lines[1], $match)) {
            // this is a tested array/recursive call to this function
            // take a set of spaces off the beginning
            $spaces = $match[1];
            $spaces_length = strlen($spaces);
            $lines_total = count($lines);
            for ($i = 0; $i < $lines_total; $i++) {
                if (substr($lines[$i], 0, $spaces_length) == $spaces) {
                    $lines[$i] = substr($lines[$i], $spaces_length);
                }
            }
        }
        array_shift($lines); // Array
        array_shift($lines); // (
        array_pop($lines); // )
        $in = implode("\n", $lines);
        // make sure we only match stuff with 4 preceding spaces (stuff for this array and not a nested one)
        preg_match_all("/^\s{4}\[(.+?)\] \=\> /m", $in, $matches, PREG_OFFSET_CAPTURE | PREG_SET_ORDER);
        $pos = array();
        $previous_key = '';
        $in_length = strlen($in);
        // store the following in $pos:
        // array with key = key of the parsed array's item
        // value = array(start position in $in, $end position in $in)
        foreach ($matches as $match) {
            $key = $match[1][0];
            $start = $match[0][1] + strlen($match[0][0]);
            $pos[$key] = array($start, $in_length);
            if ($previous_key != '') $pos[$previous_key][1] = $match[0][1] - 1;
            $previous_key = $key;
        }
        $ret = array();
        foreach ($pos as $key => $where) {
            // recursively see if the parsed out value is an array too
            $ret[$key] = print_r_reverse(substr($in, $where[0], $where[1] - $where[0]));
        }
        return $ret;
    }
}

// Other author's mod. Fix null values?
// original gist with other comments: https://gist.github.com/simivar/037b13a9bbd53ae5a092d8f6d9828bc3

/**
  * Matt: core
  * Trixor: object handling
  * lech: Windows suppport
  * simivar: null support
  *
  * @see http://php.net/manual/en/function.print-r.php
  **/
function print_r_reverse($input) {
        $lines = preg_split('#\r?\n#', trim($input));
        if (trim($lines[ 0 ]) != 'Array' && trim($lines[ 0 ] != 'stdClass Object')) {
            // bottomed out to something that isn't an array or object
            if ($input === '') {
                return null;
            }
           
            return $input;
        } else {
            // this is an array or object, lets parse it
            $match = array();
            if (preg_match("/(\s{5,})\(/", $lines[ 1 ], $match)) {
                // this is a tested array/recursive call to this function
                // take a set of spaces off the beginning
                $spaces = $match[ 1 ];
                $spaces_length = strlen($spaces);
                $lines_total = count($lines);
                for ($i = 0; $i < $lines_total; $i++) {
                    if (substr($lines[ $i ], 0, $spaces_length) == $spaces) {
                        $lines[ $i ] = substr($lines[ $i ], $spaces_length);
                    }
                }
            }
            $is_object = trim($lines[ 0 ]) == 'stdClass Object';
            array_shift($lines); // Array
            array_shift($lines); // (
            array_pop($lines); // )
            $input = implode("\n", $lines);
            $matches = array();
            // make sure we only match stuff with 4 preceding spaces (stuff for this array and not a nested one)
            preg_match_all("/^\s{4}\[(.+?)\] \=\> /m", $input, $matches, PREG_OFFSET_CAPTURE | PREG_SET_ORDER);
            $pos = array();
            $previous_key = '';
            $in_length = strlen($input);
            // store the following in $pos:
            // array with key = key of the parsed array's item
            // value = array(start position in $in, $end position in $in)
            foreach ($matches as $match) {
                $key = $match[ 1 ][ 0 ];
                $start = $match[ 0 ][ 1 ] + strlen($match[ 0 ][ 0 ]);
                $pos[ $key ] = array($start, $in_length);
                if ($previous_key != '') {
                    $pos[ $previous_key ][ 1 ] = $match[ 0 ][ 1 ] - 1;
                }
                $previous_key = $key;
            }
            $ret = array();
            foreach ($pos as $key => $where) {
                // recursively see if the parsed out value is an array too
                $ret[ $key ] = print_r_reverse(substr($input, $where[ 0 ], $where[ 1 ] - $where[ 0 ]));
            }
           
            return $is_object ? (object)$ret : $ret;
        }
    }