Errors are just values. They don't have any special meaning nor is there any special ceremony to create them. A panic must start from calling panic(); there's no function or special statement to create or return an error.
It might be possible to augment every `error`-typed return such that the concrete type is replaced by some synthetic type with a stack trace included. However, this would only work because `error` is an interface, so any function returning a concrete-typed error wouldn't be eligible for this; it would also add a lot of runtime overhead (including, at the very least, a check for nil on every return); and it would cause issues with code that still does == comparisons on errors.
On the whole, I think error-wrapping solves the problem of tracing an error well enough as the language exists today. If errors are going to start having some magic added to them, I think the entirety of error-handling deserves a rethink (which may be due, to be fair).
Errors are just values. They don't have any special meaning nor is there any special ceremony to create them. A panic must start from calling panic(); there's no function or special statement to create or return an error.
It might be possible to augment every `error`-typed return such that the concrete type is replaced by some synthetic type with a stack trace included. However, this would only work because `error` is an interface, so any function returning a concrete-typed error wouldn't be eligible for this; it would also add a lot of runtime overhead (including, at the very least, a check for nil on every return); and it would cause issues with code that still does == comparisons on errors.
On the whole, I think error-wrapping solves the problem of tracing an error well enough as the language exists today. If errors are going to start having some magic added to them, I think the entirety of error-handling deserves a rethink (which may be due, to be fair).