Go javascript engine.
go run main.go
Use environment variables to configure the engine.
GOJO_INPUT_FILE- Set file path to use it as input (default=input_program.js).GOJO_VERBOSE- Set totrueto enable verbose logging.GOJO_MEGA_VERBOSE- Set totrueto enable EVEN MORE logging.GOJO_TEST- Set totrueto run tests only.
Yo! This is for learning purposes and not intended to ever be finished.
- Lexer (FSM): Meh compliance with the ECMAScript spec.
- Parser (Recursive Descent):
- Variables
- Literals: Integers Booleans Strings
- Binary expressions
- Grouped expressions
- If/Else statements
- Basic Function declarations
- Block statements
- While statements
- Interpreter (& Go Runtime):
- Sets variable declarations of above types
- Evaluates Simple Binary expressions (+, -, *, /)
- Call expressions and translates the following to go runtime:
console.log, Math.sqrt, Math.pow, typeof
For the code var x = 1 + 1;
- Lexer: Produces a stream of tokens
var, x, =, 1, +, 1, ; - Parser: Produces an AST
Program -> Statements[] -> VariableDeclaration(x = BinaryExpression(1 + 1)) - Interpreter: Process the AST and stores the value in the environment
x = 2
- ECMAScript spec - https://tc39.es/ecma262/
- JSConf rust JS engine talk - https://youtu.be/_uD2pijcSi4
- Writing a tokenizer (not great performance wise but a start) - https://dev.to/ndesmic/writing-a-tokenizer-1j85
- General simple lexer - https://codemaster138.github.io/blog/creating-an-interpreter-part-1-lexer/
- Writing an interpreter in go - https://edu.anarcho-copy.org/Programming%20Languages/Go/writing%20an%20INTERPRETER%20in%20go.pdf
- Acorn js js parser - https://github.com/acornjs/acorn
- Standard compliant parser - https://github.com/jquery/esprima
- AST Explore - https://astexplorer.net/
- Recursive Descent Parsing: https://www.cs.rochester.edu/u/nelson/courses/csc_173/grammars/parsing.html#:~:text=Recursive-descent%20parsing%20is%20one,non-terminal%20with%20a%20procedure