creating of multi dimensional arrays with unknown depth

Hi all! I got a string which include information for categories that I need to build, the string is built like this: $string = "val1~~val2~~val3~~val4~~val5" Now, I want to create from this string a multi dimensional array and not one dimension array as explode('~~', $string) will give me. The desired result from this string is: $array['val1'] = 'whatever'; $array['val1']['val2'] = 'whatever'; $array['val1']['val2']['val3'] = 'whatever'; $array['val1']['val2']['val3']['val4'] = 'whatever'; $array['val1']['val2']['val3']['val4']['val'5] = 'whatever'; My problem is that the number of the dimensions is really unknown and can be changed from 1 to 20 as far as I know. Is there a way to create such a dynamic depth in an automatic way and not by using lots of if's? Thanks in advance, Ben-Nes Yonatan Canaan Surfing Ltd.