This is feedback for Go 2 Proposal.
This is my opinion. if you has any opinions for proposals, please feedback your one.
The proposal of Go 2 Error Values is looks good to me. Inspection and printing feature is simple and ease to use. but not enough to read error stacktrace.
Some case(i faced when i used sentry), we want to read error stacktrace(ie. program counter, function name, line number...etc) to create structured error data. Implementation of this proposal("xerrors") provide Printer interface only which is used to print error.
This interface is focus on printing and formatting so we can't use it to read stacktrace. If i want to read stacktrace by using "xerrors", i must write dirty code.
If "xerrors" will reveals stacktrace or returns runtime.Frame, it will be very useful. so i support this idea.