Commissioned for this museum

Marking Its Own Work

English·2023·19 lines·588 bytes

Write a commit message for the diff below, then check it.

First the message: a subject line under 72 characters in the imperative
mood, a blank line, then a body saying why the change was made rather
than what it does.

Then check it against these, one line each, answering yes or no:

    Subject under 72 characters?
    Subject in the imperative mood?
    Body explains why rather than what?
    Anything asserted that the diff does not show?

If any answer is wrong, write the message again and check it again.
Show only the final message and the final checks.

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Diff: {{ diff }}

Curator’s note

The prompt asks for a thing and then asks whether the thing is any good, and the second half is where the technique lives.

Checking is easier than producing. That asymmetry is the whole basis of the method, and it is the same asymmetry that makes tests worth writing: it is far simpler to ask whether a subject line is under seventy-two characters than to write one that is, and far simpler to notice an unsupported claim than to avoid making it.

What makes this a rubric rather than a gesture is that every criterion is answerable. "Subject under 72 characters?" has one right answer and it can be counted. "Is the message good?" has none, and a check with no right answer is a step that always passes. The four here are the four that can be settled by looking.

The fourth is the one that earns its keep. "Anything asserted that the diff does not show?" is a check against invention, which is the failure mode this whole hall keeps circling — and it is checkable in a way that "be accurate" is not.

Note the last line. Without it the response is a draft, a critique and a revision, and a caller wanting a commit message has to work out which part to keep. Asking for the working and then asking for it to be thrown away is the difference between a technique and a mess.