Help with Linked Lists

Here's the meat of it. I'd like to create a global TList of skill_def objects (or pointers to them, rather). I do so like this:

global skill_def_list:TList = CreateList()

And then I'd like to add my loaded skill_def objects to this list, as such:

s:skill_def = new skill_def
ListAddLast skill_def_list, s

And then I'd like to iterate through the list of objects, and reference fields, as such:

for s:skill_def = EachIn skill_def_list
print s.id
next

However, I receive the error "Identifier type does not match declared type", pointing to the "for..EachIn" line, when I try to compile/run. What am I doing wrong?