Such an editor will be written in HQ9E+, my fork of HQ9+ with the following semantics:

    H: prints Hello, World!
    Q: prints the program's source text
    9: prints the lyrics to 99 Bottles of Beer on the Wall
    E: behaves like a nano-like text editor
    +: increments the accumulator

A transparent preprocessor can of course be used to add the necessary "E" to the empty source as part of the build step.

I feel the urge to post an xkcd here. https://xkcd.com/378/

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