Remove the 1st line using a Cue Flag- is it possible?

[cueckoo]

Originally opened by @Newbie112222 in cuelang/cue#966

Hi All,
I have a use case where i use the cue export command to compare 2 files. My issue is that the final yaml file (after successfully running the export command) i generate has a field on the 1st line which i want to comment or remove from the file.
Any inputs would be appreciated:

Final File test.yaml:
config: ( <------- remove this from the final file)
url: google.com
storage:
type: postgres

[cueckoo]

Original reply by @eonpatapon in cuelang/cue#966 (comment)

You can define config as a hidden field: _config

It then won't be exported.

[cueckoo]

Original reply by @mpvl in cuelang/cue#966 (comment)

Alternatively, if config is still part of a public API, you can use #config as well.