PHP recursive function nesting level reached - php

Question

Good day. I have a parcer function that taker an array of string like this:
['str','str2','str2','*str','*str2','**str2','str','str2','str2']
And recursivelly elevates a level those starting with asterix to get this
['str','str2','str2',['str','str2',['str2']],'str','str2','str2']
And the function is:
function recursive_array_parser($ARRAY) {
do {
$i = 0;
$s = null;
$e = null;
$err = false;
foreach ($ARRAY as $item) {
if (!is_array($item)) { //if element is not array
$item = trim($item);
if ($item[0] === '*' && $s == null && $e == null) { //we get it's start and end if it has asterix
$s = $i;
$e = $i;
} elseif ($item[0] === '*' && $e != null)
$e = $i;
elseif (!isset($ARRAY[$i + 1]) || $s != null && $e != null) { //if there are no elements or asterix element ended we elevate it
$e = $e == NULL ? $i : $e;
$head = array_slice($ARRAY, 0, $s);
$_x = [];
$inner = array_slice($ARRAY, $s, $e - $s + 1);
foreach ($inner as $_i)
$_x[] = substr($_i, 1);
$inner = [$_x];
$tail = array_slice($ARRAY, $e + 1, 999) or [];
$X = array_merge($head, $inner);
$ARRAY = array_merge($X, $tail);
$s = null;
$e = null;
$err = true;
}
} else {
$ARRAY[$i] = recursive_array_parser($ARRAY[$i]); //if the item is array of items we recur.
}
$i++;
if ($err == true) {
break 1;
}
}
} while ($err);
return $ARRAY;
}
When this function runs, i get "Fatal error: Maximum function nesting level of '200' reached, aborting!" error.
I know it has something to do with infinite recursion, but i can't track the particular place where it occurs, and this is strange.

Answer 1

I don't normally rewrite code, but your code can be reduced and simplified while, from what I can see, getting the desired result. See if this works for you:
$a = array('a','b','c','*d','*e','**f','g','*h');
print_r($a);
$a = recursive_array_parser($a);
print_r($a);
function recursive_array_parser($array)
{
$ret = array();
for($i=0; $i<sizeof($array); $i++)
{
if($array[$i]{0}!='*') $ret[] = $array[$i];
else
{
$tmp = array();
for($j=$i; $j<sizeof($array) && $array[$j]{0}=='*'; $j++)
{
$tmp[] = substr($array[$j],1);
}
$ret[] = recursive_array_parser($tmp);
$i = $j-1;
}
}
return $ret;
}
Note that it isn't possible for $array[$i] to be an array, so that check is removed. The recursion takes place on the temp array created when a * is found. The $i is closer tied to $array to reset it properly after parsing the series of * elements.

Answer 2

Here's my solution. No nested loops.
function recursive_array_parser($arr) {
$out = array();
$sub = null;
foreach($arr as $item) {
if($item[0] == '*') { // We've hit a special item!
if(!is_array($sub)) { // We're not currently accumulating a sub-array, let's make one!
$sub = array();
}
$sub[] = substr($item, 1); // Add it to the sub-array without the '*'
} else {
if(is_array($sub)) {
// Whoops, we have an active subarray, but this thing didn't start with '*'. End that sub-array
$out[] = recursive_array_parser($sub);
$sub = null;
}
// Take the item
$out[] = $item;
}
}
if(is_array($sub)) { // We ended in an active sub-array. Add it.
$out[] = recursive_array_parser($sub);
$sub = null;
}
return $out;
}