Grail

Run Python on the GemStone/S 64 Bit.

Installation

Git Checkout

Checkout this GitHub project to $HOME/code/GemStone/Grail (or to some other place and be prepared to edit things to match your path).

GemStone/S

GemStone/S can be most easily run using the GemStone Smalltalk IDE (a Visual Studio Code Extension).

Copy the provided scripts/topazini to ~/.topazini and edit gs64stone to show the name of your database if different. Copy the provided scripts/setenv to .setenv and edit the path to point to your GemStone install. Then open a terminal in this directory and run ./install_base.sh (once per stone, as SystemUser) followed by ./install.sh (per user). If these finish without errors then you may proceed to the next step.

Tests

To run the test suite, run ./scripts/run_tests.sh.

Running Python Code in Grail

Hello World

Our first task is a "Hello World!" program (src/python/hello.py). From a command line execute:

./grail src/python/hello.py

REPL

A REPL (read-eval-print loop) is a convenient way to experiment with a programming language. To run the Grail REPL, execute:

./grail

To exit the REPL, enter exit() or quit(). If you get an error and end up with a topaz 1> prompt, then enter exit to exit.

GemStone Interoperability

Python code can work with existing GemStone data and operations through the built-in gemstone module:

import gemstone

gemstone["greeting"] = "Hello, Grail!"   # named globals (UserGlobals / symbol list)
gemstone.system.commit()                 # transaction control via the System class
symbol_dictionaries = gemstone.mySymbolList   # the session's SymbolDictionary instances

See The gemstone Module for the full API.

Embedded CPython (Two-Object-Space)

Grail includes an optional embedded CPython integration that loads libpython as a dynamic library via GemStone's CCallout/CLibrary FFI. This provides a "two-object-space" bridge where Python objects live in CPython's heap and are manipulated through CPythonLibrary and CPythonObject wrappers.

This is separate from the main Grail approach (single object space with native Smalltalk types) and from the CPythonShim (which loads C extension modules). If python3 is available at install time, install.sh will auto-detect and configure the library path.

Note: Both CPythonLibrary (embedded) and CPythonShim (extension shim) export CPython C API symbols. Only one may be used per Gem session; a runtime guard prevents loading both.

Other documentation

• Programs that we could use to test our work.
• Development process and notes.