PharoGs

Experimental project to bootstrap Pharo source into a GemStone db ... the basic idea is to use the same technology created for running Ruby in GemStone for running alternate Smalltalk implementations in GemStone.

The package PharoGs-Basic-ProtoObject package contains the Pharo 6.0 source (currently as of Pharo 6.0 #60332) for the ProtoObject class. The package PharoGs-Dev-ProtoObject package contains the GemStone Smalltalk source code to implement the equivalent Pharo functionality ... a Pharo primitive implemented in GemStone Smalltalk. The package PharoGs-Tode-ProtoObject package contains the GemStone Smalltalk source code to support the use of tODE for inspecting PharoGs objects.

Here's an example of a Pharo Primitive implemented in GemStone smalltalk. This is the implementation of doesNotUnderstand: method in method environment 2:

doesNotUnderstand: aMessageDescriptor
  "invoke MessageNotUnderstood indirectly in env 0"

^ self @env0: doesNotUnderstand: aMessageDescriptor

The selector @env0: allows one to call a method in an alternate method environment and in this case it is calling the doesNotUnderstand: method in method environment 0:

doesNotUnderstand: aMessageDescriptor

"The method is for compatiblity with Gs64 v2.x, and assumes you are using 
   only method environment 0  for all of your Smalltalk code."

| ex sel args |
(ex := MessageNotUnderstood _basicNew)
  receiver: self selector: (sel := aMessageDescriptor at: 1) 
		args: (args := aMessageDescriptor at: 2) envId: 0 .
^ex signal .

Screen shot of tODE environment opened on ProtoObject class, browsing method environmen 0 methods:

ProtoObject is the only class in system (CompileError occurred (error 1001), undefined symbol Object in shell window and no ProtoObject subclasses in hierarchy pane).

Note the inspector pane open on a ProtoObject instance. GemStone does not (currently) have the notion of thisContext, so I've added thisContext as an instance variable to ProtoObject, so I won't have to immediately edit methods that reference thisContext. thisContext also acts as a signature for PharoGs classes as the ProtoObject class in GsDevKit does not have that instance variable.

PharoGsUser is a GemStone user with a symbol list that contains a symbol dictionary named Smalltalk and the single class ProtoObject. The Pharo methods are installed in method environment 2 (no tODE browsing capability, yet), but you can browse the PharoGs-Basic-ProtoObject package to see the method environment 2 class and instance methods.

Here's a screen shot of a topaz session logged in as PharoGsUser:

... and here's a screen shot of a tODE debugger open on an MNU:

Installation

Use the following bash script to install PharoGs into a stone:

cd $GS_HOME/shared/repos/dev
git checkout dev
git pull origin dev
cd $GS_HOME
createStone -u http://gsdevkit.github.io/GsDevKit_home/PharoGs.ston -i PharoGs -l PharoGs PharoGs 3.4.0
cp $GS_HOME/shared/repos/PharoGs/bin/installPharoGs $GS_HOME/server/stones/PharoGs
cd $GS_HOME/server/stones/PharoGs
./installPharoGs

Rebuild clients so that they will use the dev branch of tODE:

updateGsDevKit -c

Bring up a tODE client:

startClient tode

...create the GemStone user PharoGsUser with ProtoObject class installed. Every time the script is executed the old user is destroyed and a new, freshly bootstrapped user is created :

createPharoGsUser

...create a session description for the PharoGsUser by executing the following tODE script:

/home/pharoGs/createUserSessionDescription --user=PharoGsUser

...logout of the PharoGs session and log into the PharoGsUser session and run the tODE command:

browse class --full ProtoObject

to browse the PharoGs ProtoObject class.