Code samples in the tree iterator section (p136 on)

[mattparker]

Minor typo: code sample p136 has TreeNOde instead of TreeNode

In the samples that follow (p 138, 139) you have a variable name $it and $rii for the TreeIterator and RecursiveIteratorIterator. They're a bit short for some, but it's a bit confusing because the next section talks about the "it" node - which isn't $it. So by the bottom of page 139 you're recursively iterating $it looking for "it" which is an instance of ItTreeNode... In short, some more expressive variable names here would really help clarify the example, I think!

[mattparker]

Maybe I'll be more constructive: how about something along these lines:

$theTree = new TreeIterator($rootNode);

$treeIterator = new RecursiveIteratorIterator($it, RecursiveIteratorIterator::SELF_FIRST);

foreach ($treeIterator as $treeNode) {
    if ($treeNode instanceof ItTreeNode) {
        echo 'Found it! Depth was ' . $treeIterator->getDepth();
        break;
    }
}

[Swader]

+1