When entering an invalid email in Mail's NSTokenField one get's this (a mix of token and plain string values):

alt text

Is there any recommendable way to accomplish this?
Is NSTokenField even the right tool for this? Or would I be abusing it?

In this particular project I need to allow the user to enter a file name pattern
(there are several other use cases though), with support for predefined tokens.

Right now I'm requiring the input to be entered like this:

Glue Text %[Tag]Other Glue Text%[Another Tag]More Text

I'd like to change this to some fool-proof graphical solution like this: alt text

NSTokenField always(!) turns entered text into tokens.

Either I'm using the wrong keywords in my web searches,
or I'm really the first to need this (mixed) behaviour?!

I did read thru Apple's NSTokenField Guide, but couldn't find any info on my problem.

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