## 2.2 Changes in the implementation that affect usability and performance

### 2.2.1 Oz Compiler

- Keyword `native` has been removed from class's properties. This implies a change in the module `Open` in contributions, fixing a runtime error (bug 1277).

- A warning is triggered when a non-valid property is added after keyword `fun` in function definitions. This prevents programmers from creating eager functions when keyword `lazy` is misspelled (bug 1437).

- Added `--warnshadow` option to compiler to emit warning message when variables in an outer scope are shadowed (bug 1707).

### 2.2.2 Garbage Collection

- Indexes have been fixed to work with RAM memory bigger that 1GB.

### 2.2.3 Distribution Layer

- `NewPort` does not block anymore when using a distributed variable for the stream. Currently, the builtin receives one input and one output, but it should change to two outputs in a future release (bug 1521).

- Problem with sockets generating 'segmentation fault' with P2PS is fixed (bugs 1304, 1339).

- Failed assertion in the Owner table fixed (bug 1461).