implementing a control for completing filenames with a defined list of tokens

[Eric Smith <Eric.Smith@xxxxxxxxxxxxx>]

Wise zsh'lers,

I would like to define a completion widget to complete filenames with a defined
list of tokens.  The widget would look up in a list the tokens and suggest
these (ideally in order) to the user.

As an example;

$ cat tokenfile
token1
token2
token3

User has the binding control-k to execute the completion function;

mv <somefile> <c-k>
Then the widget would supply

mv <somefile> token1
token1
token2
token3

How would I best implement this?

-- 
Eric Smith