Create nested array

[zzman]

i have a flat array with values like:

array[0] = "/fol1_level1"
array[1] = "/fol1_level1/fol1_level2"
array[2] = "/fol1_level1/fol1_level2/fol1_level3"
array[3] = "/fol2_level1"
array[4] = "/fol2_level1/fol2_level2"

...
i am trying to convert this array in to a nested one by using some kind of recursive logic that nests all related values for example:

array[0][/fol1_level1]
array[0][/fol1_level1][/fol1_level2]
array[0][/fol1_level1][/fol1_level2][/fol1_level3]
array[1][/fol2_level1]
array[1][[/fol2_level1][fol2_level2]

...
its a directory tree only thing is all the directories are stored in a database.

[bradgrafelman]

Well I was curious to see if I could do this, and the method that I came up with is... well, rather odd (I had to use eval() to start with). Here's the code:

foreach($array as $key => $value) {
	unset($array[$key]);
	eval('$array['.$key.']' . makeArray($value) . ' = NULL;');
}

function makeArray($value) {
	$arrays = array_filter(explode('/', $value));
	for($i=reset($arrays), $tmp=''; $i !== FALSE; $i=next($arrays))
		$tmp .= "['$i']";
	return $tmp;
}

and with your example array, this is the output:

Array
(
    [0] => Array
        (
            [fol1_level1] => 
        )
    [1] => Array
        (
            [fol1_level1] => Array
                (
                    [fol1_level2] => 
                )
        )
    [2] => Array
        (
            [fol1_level1] => Array
                (
                    [fol1_level2] => Array
                        (
                            [fol1_level3] => 
                        )

            )

    )
[3] => Array
    (
        [fol2_level1] => 
    )
[4] => Array
    (
        [fol2_level1] => Array
            (
                [fol2_level2] => 
            )
    )
)

[Weedpacket]

I wanna have a turn.

Okay, this is the second attempt; the first was ghastly and convinced me there had to be a cleaner solution, probably involving recursion.

function make_arrays($array)
{
	foreach($array as $k=>$path)
	{
		$array[$k] = array_filter(explode('/', $path));
	}
	return make_arrays_aux($array);
}

function make_arrays_aux($array)
{
	$new_array = array();
	foreach(array_filter($array) as $path)
	{
		$dir = array_shift($path);
		$new_array[$dir][]=$path;
	}
	if(!count($new_array)) return null;
	return array_map('make_arrays_aux',$new_array);
}

The output of that is

Array
(
    [fol1_level1] => Array
        (
            [fol1_level2] => Array
                (
                    [fol1_level3] =>
                )

    )

[fol2_level1] => Array
    (
        [fol2_level2] =>
    )

)

[zzman]

Thanks ... ill try it out ....

[zzman]

This should do it ...

//create the nested array
foreach ($all_physical_folders as $path) {
	eval('$paths[\''.implode('\'][\'', array_filter(explode('/', $path))).'\'] = "";');
}