This project provides a playground where you can
evaluate arbitrary Smalltalk (ST) expressions and see the results.
First run startWebBrowser.sh to start a static web server.
Before the app is started, all ST sources are compiled first.
Now enter an arbitrary ST expression in the expression text area and press [>Evaluate] to see the result below. This is handy for learning SmallJS and real-time testing.
Expressions are evaluated locally in the browser.
For a new expression a slightly modified version of the compiler is used that compiles to memory. Before compilation the array of compiled class names is fetched from the file:
Smalltalk/CompiledClassesJson.js to be able to check references to class name references.
The evaluated expression is then put into temporary class Evaluator in the method evaluate.
This class is compiled to memory and put in a HTML <script> node on the page ending with some JS code that calls the evaluate function and catches the async result in a callback.
If the compiler changes, it needs to be re-ported to the playground with a few changes.
The leading source files of the compiler are in the folder /Compiler/src.
Overwrite sources files with the same names as in /Playground/src/Compiler.
Then search for the string “Playground” in the sources to see where code needs to be adjusted.
Note that the file /Playground/src/Compiler/SourceNode.ts is unique to the Playground.
This is a limited implementation of the npm package source-node
that only manages source trees but does not generate (unneeded) source map files.