Considering 418 is the positive assertion, suddenly reversing that would break backwards compatibility; additionally, it adds ambiguity by listing multiple entities it is not, leaving the receiver to potentially assume that it is, for example, a microwave.
EDIT: missed the positive part remaining, sorry. I maintain that the ambiguity issue stands.
For compatibility with header splitting, the delimiter should be a comma, The following header:
I'm-Not-A: freezer, teapot, radio
is equivalent to:
I'm-Not-A: freezer
I'm-Not-A: teapot
I'm-Not-A: radio
even in cases where the client, server, or some intermediate proxy doesn't know the I'm-Not-A header.
[−]jagged-chisel · 2026-11-15 Sun 18:34 UTC ·
link
This is unwieldy. Now my server has to list everything is is not.
It's not a quasar, nor a toaster, nor a tree, a pipe, a microwave transmitter, a microwave oven, a plush spider, an actual arachnid, a whale, a motorscooter, a motorcycle, an automobile, an apricot, a grape, raw sugar ...
EDIT: missed the positive part remaining, sorry. I maintain that the ambiguity issue stands.
It's not a quasar, nor a toaster, nor a tree, a pipe, a microwave transmitter, a microwave oven, a plush spider, an actual arachnid, a whale, a motorscooter, a motorcycle, an automobile, an apricot, a grape, raw sugar ...
That response would be a lie, though. If it runs on electricity, it's most definitely a radio of some sort.