scala/scala — pull request #1303 by paulp (2012-09-14 15:58:22+00:00)
Title: Eliminate breaking relative names in source.

These things are killing me. Constructions like

package scala.foo.bar.baz
import foo.Other

DO NOT WORK in general. Such files are not really in the
"scala" package, because it is not declared

package scala
package foo.bar.baz

And there is a second problem: using a relative path name means
compilation will fail in the presence of a directory of the same
name, e.g.

% mkdir reflect
% scalac src/reflect/scala/reflect/internal/util/Position.scala
src/reflect/scala/reflect/internal/util/Position.scala:9: error:
object ClassTag is not a member of package reflect
import reflect.ClassTag
^
src/reflect/scala/reflect/internal/util/Position.scala:10: error:
object base is not a member of package reflect
import reflect.base.Attachments
^

As a rule, do not use relative package paths unless you have
explicitly imported the path to which you think you are relative.
Better yet, don't use them at all. Unfortunately they mostly work
because scala variously thinks everything scala.* is in the scala
package and/or because you usually aren't bootstrapping and it
falls through to an existing version of the class already on the
classpath.

Making the paths explicit is not a complete solution -
in particular, we remain enormously vulnerable to any directory
or package called "scala" which isn't ours - but it greatly
limts the severity of the problem.