phelt

phelt is a toy programming language.

Features

phelt is based on Monkey, as implemented in the Interpreter Book, with the following additions:

• Run code from files, not just a REPL.
• Improved error reporting, including line and column information.
• 64 bit Floats & Integers.
• Infix assignment operators =, +=, -=, *= /=.
• Additional comparsion operators, <=, >=.
• do { } blocks for scoped expressions.
• For loops, for(initial; condition; final) { break; } & while loops, `while(condition) { break; }`.
• eval() for executing code from string input.
• Arrays are mutable, with an extended array toolset.
• Truly constant constants, once defined they can never be redefined, regardless of scope.
• Fully reworked hashes. Hash keys are limited to identifiers and integers. You can access as well as index hash entries, hash.entry or hash["entry"] both work.
  • This allows for some level of pseudo-class functionality.
  • This may be expanded upon in the future by implementing meta-functions on hashes.
• Pseudo object functionality built using hashes.
  • When calling a function on an object (eg. [1, 2, 3].first), the functions object type is mapped to an internal hash. The hash stores functions callable on that object type.
  • See environment.ph for functionality built unsing phelt it's self.

Installation

Once you have Crystal setup locally, simply run:

shards build phelt

The phelt interpreter can be found in the bin/ directory.

Usage

Usage: phelt [command] [program file]
    -v, --version                    Show version
    -h, --help                       Show help
    -d, --debugger                   Interactive Debugger
    -i, --interactive                Interactive REPL

Contributing

1. Fork it (https://github.com/benphelps/phelt/fork)
2. Create your feature branch (git checkout -b my-new-feature)
3. Commit your changes (git commit -am 'Add some feature')
4. Push to the branch (git push origin my-new-feature)
5. Create a new Pull Request

Contributors

• Ben Phelps - creator and maintainer