Arrays with Dynamic Dimensions

[tomcatexodus]

What is the easiest way to see how many dimensions an array has?

The reason is, I'm trying to create a sort of node tree, and as my data parser reads deeper in a file, it needs to add to an array like this:

$node[0] = "a node"; 

then, the next child would be:

$node[0][0] = "a child"; 

...and eventually I'm pretty far from home:

$node[3][0][0][5] = "some pretty deep data"; 

Since there is no way to tell the number of children that a file may generate in parsing, at times I need to find out how deep I am, achieving the code snippets above?