git @ Cat's Eye Technologies Robin / 0.2-2018.1029

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This is a work in progress

Robin is a homoiconic S-expression-based language (similar to, for example, Scheme, with influences from Pixley and PicoLisp) with the following features:

  • The macro (rather than the function) as the fundamental abstraction mechanism. There is a function form, but it's defined as a macro!
  • A very small set of built-in operations.
  • A very small reference implementation in Literate Haskell (about 600 lines of code, excluding the explanatory prose.)
  • A fairly rich standard library of macros built on top of those built-in operations. (Thus it can be used as either a "low-level" or "high-level" language.)
  • A fairly rich test suite (about 460 test cases.)
  • An almost zealous system-agnosticism.
  • An almost zealous disdain for escape characters. Robin's string syntax never needs them (it's more like a lightweight "heredoc".)
  • A module system (which is rather fast-and-loose, so it's perhaps not fair to call it a module system. It's more like C's #includes — except it's zealously system-agnostic. And actually we're still working out the details here. See the file doc/Modules.markdown.)
  • A(n attempt at) a clean separation of evaluation (no "side-effects") and execution (with "side-effects" and system interaction) by the use of reactors (which are basically event handlers.) See the file doc/Reactor.markdown for more information.

Quick Start

You'll need either ghc or Hugs installed.

Clone this repo and cd into it, and run ./ to build the reference interpreter bin/robinri, and the slightly-less-impractical interpreter called bin/whitecap (for historical reasons, and subject to change.)

(Or if you have toolshelf, just run toolshelf dock gh:catseye/robin.)

If you have a few minutes to spare, please do run the tests by running ./ (This requires Falderal.)

(There will be a link to a tutorial with further instructions in the future)


Robin's fundamental semantics are documented in doc/Robin.markdown.


Robin 0.2 is a somewhat significant departure from Robin 0.1. It keeps:

  • its syntax
  • its core builtins (mostly)
  • some of its standard modules ("small", list, environment, boolean, arith)
  • exceptions (and makes them standard rather than optional)
  • its zealous system agnosticism
  • its zealous disdain for escape characters (i.e. its literal string syntax)

Robin 0.2 discards from Robin 0.1:

  • bigrats. Instead, in Robin 0.2 you get 32-bit signed integers (yes, precisely those.) Anything else, you have to build.
  • its module system. Robin has its own, much less hermetic/holistic system. See the file doc/Modules.markdown.
  • concurrency.
  • I/O and side-effects. It has reactors instead. See doc/Reactor.markdown.
  • its grand ambitions. Robin would rather exist than be perfect.

Robin 0.2 adds to Robin 0.1:

  • reactors, which I hope will be a cleaner and more system-agnostic way to do I/O. See doc/Reactor.markdown.