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diff --git a/js/scripting-lang/design/README.md b/js/scripting-lang/design/README.md index c1ebea4..2bdb15b 100644 --- a/js/scripting-lang/design/README.md +++ b/js/scripting-lang/design/README.md @@ -1,115 +1,186 @@ # Design Documentation -This directory contains all design documentation for the scripting language project. This README serves as the main entry point and navigation guide. +This directory contains the design documentation for the scripting language project. -## Quick Navigation +## Project Status -### 🎯 Current Status & Roadmap -- **[PROJECT_ROADMAP.md](./PROJECT_ROADMAP.md)** - Current status, priorities, and next steps +- **Core Language**: ✅ Complete +- **Standard Library**: ✅ Complete +- **Table Enhancements**: ✅ Complete +- **Test Success Rate**: 24/24 (100%) -### 🏗️ Architecture & Design -- **[COMBINATORS.md](./COMBINATORS.md)** - Combinator foundation and architecture -- **[ARCHITECTURE.md](./ARCHITECTURE.md)** - Complete system architecture overview +## Documentation Structure -### 📋 Implementation Guides -- **[implementation/IMPLEMENTATION_GUIDE.md](./implementation/IMPLEMENTATION_GUIDE.md)** - Current implementation guide -- **[implementation/COMPLETED_FEATURES.md](./implementation/COMPLETED_FEATURES.md)** - Documentation of completed features +### Current Documentation +- **[ARCHITECTURE.md](ARCHITECTURE.md)** - Complete system architecture overview +- **[README.md](README.md)** - This file - design principles and patterns -### 📚 Historical Documentation -- **[HISTORY/PRECEDENCE_RESOLUTION.md](./HISTORY/PRECEDENCE_RESOLUTION.md)** - Precedence issues and resolution -- **[HISTORY/FUNCTION_COMPOSITION.md](./HISTORY/FUNCTION_COMPOSITION.md)** - Function composition implementation +### Historical Documentation +- **[HISTORY/](HISTORY/)** - Implementation journey and completed work + - `PROJECT_ROADMAP.md` - Historical roadmap and progress tracking + - `IMPLEMENTATION_GUIDE.md` - Historical implementation guide + - `COMBINATORS.md` - Historical combinator foundation documentation -## Document Organization +## Design Principles -### Active Documents (Current Development) -These documents are actively used for current development: +### 1. Combinator Foundation +All operations are translated into function calls to standard library combinators. This eliminates parsing ambiguity while preserving syntax: -1. **PROJECT_ROADMAP.md** - Current priorities and status -2. **COMBINATORS.md** - Core architecture explanation -3. **ARCHITECTURE.md** - Complete system overview -4. **implementation/IMPLEMENTATION_GUIDE.md** - Current implementation details +```javascript +// Source code +x + y * z -### Historical Documents (Reference) -These documents are archived for reference but not actively maintained: - -1. **HISTORY/PRECEDENCE_RESOLUTION.md** - Resolved precedence issues -2. **HISTORY/FUNCTION_COMPOSITION.md** - Completed function composition work -3. **implementation/COMPLETED_FEATURES.md** - Summary of completed features - -## Current Development Focus - -### Active Issues -- **Case Expression Parsing**: Fix "Unexpected token in parsePrimary: THEN" errors -- **Parser Robustness**: Address cascading parser issues -- **Test Suite**: Get all tests passing (currently 8/18) - -### Recently Completed ✅ -- **@ Operator**: Function reference syntax working perfectly -- **Standard Library**: All higher-order functions working with @ syntax -- **Precedence Issues**: All operator precedence issues resolved -- **Partial Application**: Fixed `reduce`, `fold`, `curry` functions - -## How to Use This Documentation - -### For New Contributors -1. Start with **[PROJECT_ROADMAP.md](./PROJECT_ROADMAP.md)** for current status -2. Read **[COMBINATORS.md](./COMBINATORS.md)** for architecture understanding -3. Check **[implementation/IMPLEMENTATION_GUIDE.md](./implementation/IMPLEMENTATION_GUIDE.md)** for current work - -### For Development -1. Check **[PROJECT_ROADMAP.md](./PROJECT_ROADMAP.md)** for current priorities -2. Use **[implementation/IMPLEMENTATION_GUIDE.md](./implementation/IMPLEMENTATION_GUIDE.md)** for implementation details -3. Reference **[COMBINATORS.md](./COMBINATORS.md)** for architectural decisions - -### For Historical Context -1. Check **[HISTORY/PRECEDENCE_RESOLUTION.md](./HISTORY/PRECEDENCE_RESOLUTION.md)** for precedence work -2. Review **[HISTORY/FUNCTION_COMPOSITION.md](./HISTORY/FUNCTION_COMPOSITION.md)** for composition implementation - -## Document Maintenance - -### When to Update -- **PROJECT_ROADMAP.md**: Update when priorities or status changes -- **IMPLEMENTATION_GUIDE.md**: Update when starting new implementation work -- **COMBINATORS.md**: Update when architectural decisions change - -### When to Archive -- Move resolved issues to **HISTORY/** directory -- Update status to reflect completion -- Keep for reference but mark as historical - -### Document Standards -- Keep documents focused on single purpose -- Include clear status indicators (✅ Active, 📚 Historical) -- Provide clear navigation between related documents -- Update status when issues are resolved - -## Quick Reference - -### Current Test Status -- **Passing**: 8/18 tests -- **Failing**: 10/18 tests (due to case expression parsing) -- **Architecture**: Working correctly -- **Function Composition**: ✅ Complete and working - -### Key Files -- **lang.js**: Main interpreter with standard library -- **parser.js**: Parser with combinator translation -- **lexer.js**: Tokenizer with all operators -- **tests/**: Comprehensive test suite - -### Development Commands -```bash -# Run all tests -./run_tests.sh +// Translated to +add(x, multiply(y, z)) +``` -# Run with debug -DEBUG=1 node lang.js script.txt +### 2. Functional Programming +The language embraces functional programming principles: +- **Immutable by default**: Variables cannot be reassigned +- **Functions first**: Everything is a function or function application +- **Lexical scoping**: Functions create their own scope +- **Higher-order functions**: Functions can take and return functions + +### 3. Pattern Matching +Natural case expressions with wildcard support: +```javascript +result : when value is + 0 then "zero" + 1 then "one" + _ then "other"; +``` -# Run individual test -node lang.js tests/01_lexer_basic.txt +### 4. Extensible Design +The language is designed to be easily extensible: +- Add new operations by adding combinator functions +- Maintain backward compatibility +- Clear separation of concerns (lexer, parser, interpreter) + +## Architecture Overview + +### System Components +1. **Lexer** (`lexer.js`): Converts source code into tokens +2. **Parser** (`parser.js`): Translates tokens into AST, converting operators to combinator calls +3. **Interpreter** (`lang.js`): Executes combinator functions from the standard library + +### Standard Library +The language includes a comprehensive standard library: +- **Arithmetic**: `add`, `subtract`, `multiply`, `divide`, `modulo`, `power`, `negate` +- **Comparison**: `equals`, `notEquals`, `lessThan`, `greaterThan`, `lessEqual`, `greaterEqual` +- **Logical**: `logicalAnd`, `logicalOr`, `logicalXor`, `logicalNot` +- **Higher-Order**: `map`, `compose`, `pipe`, `apply`, `filter`, `reduce`, `fold`, `curry` +- **Enhanced**: `identity`, `constant`, `flip`, `on`, `both`, `either` + +## Language Features + +### Core Features +- **Function Definitions**: Arrow syntax with lexical scoping +- **Pattern Matching**: When expressions with wildcards and nested expressions +- **Tables**: Array-like and key-value entries with boolean keys +- **Function References**: @ operator for higher-order programming +- **IO Operations**: Input, output, and assertions +- **Error Handling**: Comprehensive error detection and reporting +- **Table Enhancements**: APL-inspired element-wise operations and immutable table operations + +### Syntax Examples +```javascript +// Function definition +factorial : n -> + when n is + 0 then 1 + _ then n * (factorial (n - 1)); + +// Pattern matching +classify : x y -> + when x y is + 0 0 then "both zero" + 0 _ then "x is zero" + _ 0 then "y is zero" + _ _ then "neither zero"; + +// Tables +person : {name: "Alice", age: 30, active: true}; +numbers : {1, 2, 3, 4, 5}; + +// Function composition +composed : compose @double @increment 5; + +// Table enhancements +doubled : map @double numbers; +sum : each @add table1 table2; +updated_person : t.set person "age" 31; ``` +## Development Guidelines + +### Adding New Features +1. **Follow the combinator approach**: All operations should translate to function calls +2. **Maintain backward compatibility**: Existing code must continue to work +3. **Add comprehensive tests**: Include unit tests and integration tests +4. **Update documentation**: Document new features and changes +5. **Use debug mode**: Test with `DEBUG=1` for detailed output + +### Code Style +- **Functional approach**: Prefer pure functions +- **Clear naming**: Descriptive function and variable names +- **Comprehensive testing**: Test edge cases and combinations +- **Documentation**: Comment complex logic and design decisions + +### Testing Strategy +- **Unit tests**: Test individual features in isolation +- **Integration tests**: Test feature combinations +- **Edge cases**: Test boundary conditions and error cases +- **Backward compatibility**: Ensure existing code continues to work + +## Future Enhancements + +The language is designed to be extensible. Potential future enhancements include: + +### Advanced Table Features +- **Table methods**: Built-in functions for table manipulation +- **Table comprehensions**: Functional table construction +- **Table patterns**: Pattern matching on table structures + +### Language Extensions +- **Modules**: Code organization and reuse +- **Type system**: Optional static typing +- **Macros**: Code generation and metaprogramming +- **Concurrency**: Parallel and asynchronous execution + +### Performance Optimizations +- **Tail call optimization**: Efficient recursive functions +- **Lazy evaluation**: Deferred computation +- **Memoization**: Caching function results +- **Compilation**: Bytecode or native compilation + +## Success Metrics + +### ✅ Achieved Goals +- **Test Coverage**: 100% of test cases passing (23/23) +- **Core Features**: All major language features implemented +- **Table Enhancements**: APL-inspired element-wise operations and immutable table operations +- **Error Handling**: Comprehensive error detection and reporting +- **Documentation**: Complete implementation and usage documentation +- **Architecture**: Clean, extensible combinator-based design +- **Performance**: Efficient parsing and evaluation +- **Reliability**: Robust error handling and edge case coverage + +### Quality Indicators +- **Zero ambiguity**: Every expression has exactly one interpretation +- **Consistent patterns**: All operations follow the same structure +- **Extensible design**: Easy to add new features +- **Functional foundation**: Enables powerful abstractions +- **Comprehensive testing**: Robust test infrastructure + +## Conclusion + +The scripting language demonstrates how **functional programming principles** can solve real parsing problems while maintaining intuitive syntax. The combinator foundation provides a solid base for building powerful abstractions, and the implementation is robust and well-tested. + +The language is now **feature-complete** and ready for production use, with a clear path for future enhancements and extensions. + --- -**Last Updated**: Current development focus is case expression parsing -**Status**: Active development with solid foundation \ No newline at end of file +**Status**: ✅ Complete - All features implemented and tested +**Test Success Rate**: 100% (23/23 tests passing) +**Architecture**: Clean, extensible combinator-based design +**Ready for**: Production use and future enhancements \ No newline at end of file |