When designing a macro, what is the best error type to throw for what could be see

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When designing a macro, what is the best error type to throw for what could be seen as a “syntax error”?

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in DataFramesMeta we throw ArgumentErrors, I guess because the macros in DataFramesMeta are “functon-like”.

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Dhairya 17 hours ago

Depends on the context. If you’re producing invalid regular Julia then the compiler would error for you, if it’s a DSL, then you might want to throw a custom exception if you can catch the exact issue - that would be more informative, or else an ErrorException would do

Heetbeet 17 hours ago

Thanks, yes it’s a DSL. I think I’ll then go with ErrorException

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I see ErrorException is basically the same type of error you would get with an actual syntax error. So that is probably the closest to the real deal, but ArgumentError is probably the most helpful when you are in the pre-processing the macro arguments phase.

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