It would be really cool if the Editor had a user-land "plugin" feature so developer can add behavior triggered by annotations.

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We currently support "build.dart" as a mechanism for generating errors, warnings, and other files based upon annotations and other content in the Dart source files.... which addresses comment 1.

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What is the mechanism for reporting warnings/errors via build.dart?

What is the mechanism for reporting warnings/errors via build.dart?

There isn't one. I'm not sure what Dan meant by his comment, but there isn't currently any way to add warnings and errors. Adding such a mechanism is certainly something on our radar, but unfortunately not something we're likely to get to before the end of Q1.

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This comment was originally written by nb...@gmail.com

I would be happy with an editor only annotation provided it wouldn't require manual setup for the consumer of your library and it worked with dartdoc.

Clearly there is interest here: https://code.google.com/p/dart/issues/detail?id=3193

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This comment was originally written by george.moscho...@gmail.com

This looks like a good workaround, I really miss overridable 'private' methods.

This is now in the meta package. See: #25841.