What steps will reproduce the problem? 1. package xy.C where ... 2. 3.

What is the expected output? What do you see instead?

javac complains

build\C.java:56: C is already defined in ... public static interface C {

Please use labels and text to provide additional information.

This is caused by the interface C { ... } which is nested in the outer class. This interface is built by the compiler as namespace for constants.

Probable fix: in code generation make sure that this name never conflicts with the package name.

Workaround: don't call a package just C.

The problem is even more complex, because as the Java Language Specification states in section 8.1: A compile-time error occurs if a class has the same simple name as any of its enclosing classes or interfaces.

Therefore, also the following program fails:

{{{ package TS where

data S = M | O }}}

And the following fails too:

package DX where

data D = M | O | TS | X Int

Fix posted with revision 138. This change is not backward compatible, it invalidates all code compiled so far. Therefore, a new frege3...jar will be uploaded.