fixed. :P

gistfile1.txt

// Things I don't want to see.
func (r *loadCmdReader) Next() (cmd loadCmd, err error) {
  try(
  	r.offset = r.next
      r.f.Seek(r.offset, 0)
  	binary.Read(r.f, r.order, &cmd)
  )
}

// And, believe me, if I don't see the above because it's illegal or something, then we'll definitely see this:
func (r *loadCmdReader) Next() (cmd loadCmd, err error) {
  try(func() err {
  	r.offset = r.next
      r.f.Seek(r.offset, 0)
  	binary.Read(r.f, r.order, &cmd)
  })
}