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fix: remove major mistakes in README

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TopchetoEU 2023-12-24 14:31:50 +02:00
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README.md
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@ -2,44 +2,28 @@
**NOTE: This had nothing to do with Microsoft's dialect of EcmaScript** **NOTE: This had nothing to do with Microsoft's dialect of EcmaScript**
**WARNING: Currently, this code is mostly undocumented. Proceed with caution and a psychiatrist.** **WARNING: Currently, this code is undocumented. Proceed with caution and a psychiatrist.**
JScript is an engine, capable of running EcmaScript 5, written entirely in Java. This engine has been developed with the goal of being easy to integrate with your preexisting codebase, **THE GOAL OF THIS ENGINE IS NOT PERFORMANCE**. My crude experiments show that this engine is 50x-100x slower than V8, which, although bad, is acceptable for most simple scripting purposes. Note that although the codebase has a Main class, this isn't meant to be a standalone program, but instead a library for running JavaScript code. JScript is an engine, capable of running EcmaScript 5, written entirely in Java. This engine has been developed with the goal of being easy to integrate with your preexisting codebase, **THE GOAL OF THIS ENGINE IS NOT PERFORMANCE**. My crude experiments show that this engine is 50x-100x slower than V8, which, although bad, is acceptable for most simple scripting purposes. Note that although the codebase has a Main class, this isn't meant to be a standalone program, but instead a library for running JavaScript code.
## Example ## Example
The following will create a REPL using the engine as a backend. Not that this won't properly log errors. I recommend checking out the implementation in `Main.main`: The following is going to execute a simple javascript statement:
```java ```java
var engine = new Engine(true /* false if you dont want debugging */); var engine = new Engine(false);
var env = new Environment(null, null, null); // Initialize a standard environment, with implementations of most basic standard libraries (Object, Array, Symbol, etc.)
var debugger = new DebugServer(); var env = Internals.apply(new Environment());
// Create one target for the engine and start debugging server
debugger.targets.put("target", (socket, req) -> new SimpleDebugger(socket, engine));
debugger.start(new InetSocketAddress("127.0.0.1", 9229), true);
// Queue code to load internal libraries and start engine // Queue code to load internal libraries and start engine
engine.pushMsg(false, null, new Internals().getApplier(env)); var awaitable = engine.pushMsg(false, env, new Filename("tmp", "eval"), "10 + Math.sqrt(5 / 3)", null);
engine.start(); // Run the engine on the same thread, until the event loop runs empty
engine.run(true);
while (true) { // Get our result
try { System.out.println(awaitable.await());
var raw = Reading.read();
if (raw == null) break;
// Push a message to the engine with the raw REPL code
var res = engine.pushMsg(
false, new Context(engine).pushEnv(env),
new Filename("jscript", "repl.js"), raw, null
).await();
Values.printValue(null, res);
}
catch (EngineException e) { Values.printError(e, ""); }
catch (SyntaxException ex) {
System.out.println("Syntax error:" + ex.msg);
}
catch (IOException e) { }
}
``` ```
## NOTE:
To setup the typescript bundle in your sources, run `node build.js init-ts`. This will download the latest version of typescript, minify it, and add it to your src/assets folder. If you are going to work with the `node build.js debug|release` command, this is not a necessary step.