As part of our efforts to update error messages (which, if you're interested you can go here to get involved), one of the things that still needs work are the macro errors. In the current version of "new format" these haven't been updated, and still look like the old format.
This was intentional to "encourage" me to see if we can come up with a better solution.
Today, macro errors can come out of seemingly simple code, like what someone might type in a "hello world" example.
Gives us:
In asking around, I get the sense that relatively few people use the macro errors as they stand today. That's not to say it doesn't have its users, but I think we should see what the specific needs of those people are so we can address them.
Here are the issues as I see them today:
They're relatively cumbersome, especially for new users
This is because they focus on macro writing rather than macro using
For macro users, they often describe unnecessary parts of the macro expansion
There are a couple directions to take, but I wanted to leave it relatively open. In general, I see:
We can shrink macro errors up and focus on the macro using case.
If we go that route, we could potentially have a "macro verbose" mode that can be enabled for macro writers
We can tell the macro error story a bit better using the new format