On Fri, Jan 9, 2015 at 8:15 PM, Marcus Denker <marcus.denker@inria.fr> wrote:

Hi,

After some searching for a solution�� that does not break backward-compatibility, I found a way to save classes that use
slots.

- if a class just uses ivar Slots, it saves it 100% backward compatible (e.g. loadable in other systems)
- if a class uses a special slot or class var, it saves the definition of the slot as the variable name in the
�� monticello model.
- on load it checks if there is a space in a variable name, and if yes ��> decode these as Slot/Global var definions.
- the code path for non-Slot classes stays largely untouched.

This is not beautiful but backward compatible�� you can even load classes with Slots in Pharo3, it then creates invalid
ivar names, which of course means the code does not run but it is readable.

e.g. create a class like

Object subclass: #A
�� slots: { #iv => TestSlot }
�� classVariables: {�� }
�� category: 'Playground��

(TestSlot is a slot that does not use up space in the instance and instead saves the state in the Slot object, which
means all instances share the state. Just a small example)

Limitations
�� -> no support for class variables yet
�� -> class instance variables not yet done, either
�� -> nut used much, for sure there will be bugs

This is in 4.0 438

�� Marcus

www.tudorgirba.com

"Every thing has its own flow"