code review 7379052: go/types: more robust imports

go/types: more robust imports

- imported objects don't have position information
- gc exported data contains non-exported objects at
  the top-level, guard against them
- better error message when dot-imports conflict
  with local declarations

[gri, 2013-02-26 02:04:16]

Hello adonovan@google.com, r@golang.org (cc: golang-dev@googlegroups.com),

I'd like you to review this change to
https://code.google.com/p/go

[adonovan, 2013-02-26 04:31:10]

LGTM

https://codereview.appspot.com/7379052/diff/4001/src/pkg/go/types/resolve.go
File src/pkg/go/types/resolve.go (right):

https://codereview.appspot.com/7379052/diff/4001/src/pkg/go/types/resolve.go#...
src/pkg/go/types/resolve.go:23: // for dot-imports, local declarations are
declared first - swap messages
Why is that?

[gri, 2013-02-26 04:34:10]

https://codereview.appspot.com/7379052/diff/4001/src/pkg/go/types/resolve.go
File src/pkg/go/types/resolve.go (right):

https://codereview.appspot.com/7379052/diff/4001/src/pkg/go/types/resolve.go#...
src/pkg/go/types/resolve.go:23: // for dot-imports, local declarations are
declared first - swap messages
On 2013/02/26 04:31:10, adonovan wrote:
> Why is that?

Because imports are processed after local declarations have been handled, so the
alt object's position is the position of the local object and more useful when
showing an error.

When all resolution is done in the type-checker, this should all get simpler. At
this point it's more important to provide a useful error message.

[gri, 2013-02-26 04:43:43]

*** Submitted as https://code.google.com/p/go/source/detail?r=6cc3df6d98e3 ***

go/types: more robust imports

- imported objects don't have position information
- gc exported data contains non-exported objects at
  the top-level, guard against them
- better error message when dot-imports conflict
  with local declarations

R=adonovan, r
CC=golang-dev
https://codereview.appspot.com/7379052