I downloaded this tool to try it out, but got a runtime error instead. When I try it on some other directories, I get the same error about importing other packages such as 'errors' 'fmt' and 'reflect'. (I do not get any build errors.)
```sh
go get -u github.com/jba/errside
errside github.com/jba/errside
github.com/jba/errside/: github.com/jba/errside/errside.go:4:2: could not import flag (/usr/lib/google-golang/pkg/linux_amd64/flag.a: cannot import, possibly version skew (unknown export format version 5 ("version 5")) - reinstall package)
```
go version go1.10.2 linux/amd64
Thanks for trying this.
I wrote errside as a proof of concept for my [GopherCon 2017 lightning talk](https://www.youtube.com/watch?v=_wW2U9SGKKI). It wasn't intended to be production code, and (as you've found) it doesn't work in many cases.
It's hard to maintain in its current form because it uses forks of a few standard library packages.
If you run it under go 1.8 on the testdata directory, you'll see how it's intended to work. Here's an easy way to do that with docker:
```
docker run -v $GOPATH/src:/go/src golang:1.8 go run src/github.com/jba/errside/errside.go src/github.com/jba/errside/testdata
```