important but invisible differences with texmacs preamble macros

I had a macro that didn't work until I re-typed it from scratch leading me
to discover the issue that different macros can look identical

In the preamble I have:

    <\assign|sj-info-list>
      <\macro|items>
        <\itemize-sj-info-i>
          <map-args|sj-item|document|items>
        </itemize-sj-info-i>
      </macro>
    </assign>

    <assign|sj-info-list-good|<\macro|items>
      <\itemize-sj-info-i>
        <map-args|sj-item|document|items>
      </itemize-sj-info-i>
    </macro>>

They look different, but in the editor they look the same.

[image: image.png]
Only the -good one works.

The other one renders as:
[image: image.png]
What's broken here, and why is it not possible to see the error in the
source view of the editor?

Sam