Sy: Dynamic Scripting Language for Java ME

Sy is a fork of murlen's fscriptME. The entire parser has been rewritten entirely, the interpreter removed, AST compiler added, syntax updated, and overall the code updated to be much more expandable and readable.

Features

First class functions
Compile once, run any time
One-line control structures and function definitions
loads of builtin math functions
Compile-time syntax check
Potential Parellel execution support

Implementation and Performance

The interpreter included in the original fscriptME has been removed. A AST compiler has been added in its place. Now new code will have some minor compilation overhead, but frequently used functions will run much faster. Further optimation in the LexAnn might be desirable to achieve better performance. Help will be very appreciated in this aspect.

Future Roadmap

Bug fixing and more optimizations
Landing vector and Matrix support
Support for lazy evaluation and pass-by-name
Complete unit test code

Usage

Sy scriptObject = new Sy()
scriptObject.addLines(expression);
scriptObject.parse();
SyObject result = scriptObject.run();

For detailed documentations, refer to Sy.java.

Syntax

Variable and literals

Variable are defined as they are given values, for example:

integer = 10
float = 3.2
boolean = 1 # true is 1, false 0
hello = "hello world"

Operators

+, -, *, /, %, =, ==, >, <, >=, <=, &&, || work as you expect

^ is for power. No bitwise operators are supported

Block structures

if and while can either be single-line or multiline, for example:

if a == 1: doSomething()

while 1: deadLoop()

while b = 2
  doSomethingElse(b)
end

if today == "saturday" && today == "sunday"
  sleep()
else if today == "friday"
  party()
else
  work()
end

Functions

Functions in Sy is first class, meaning that you can assign functions to variables. They can be defined in multiple ways:

square(x) = x^2

func square(x) = x^2

func square(x)
  x^2
end

To assign to global variables in local scope, use global, for example:

func globalInjection()
  global spy = "I'm a spy"
end

Comments

# is used for comments

Builtins

abs(), ceil(), floor(), sqrt(), sin(), cos(), tan(), toDeg(), toRad(), exp(), ln(), log(), asin(), acos(), atan(), random(), LN2, LN10, LOG2E, LOG10E, SQRT1_2, SQRT2, e, pi are available and work as you expect

Unit Test

The unit test code is located at /src/sy/Sy/test

xkxx / Sy