Welcome to the future (of the past)

TimL is a Lisp dialect implemented in and compiling down to VimL, the scripting language provided by the Vim text editor. Think Clojure meets VimL.

Is this a joke?

If you mean the 6,000 lines of working code, then no, I poured hundreds upon hundreds of very serious hours into that. But if you're referring to the fact it's woefully underdocumented, adds considerable overhead to an already slow host platform, and ultimately unlikely to gain any traction, then yeah, probably.

Language features

• Clojure like syntax and API, including everything from rich syntax literals to destructuring.
• Namespaces, including refer and alias.
• timl.core, a tiny but growing API resembling clojure.core.
• The same persistent collection types and interfaces, including vectors, hash maps, hash sets, lists, and lazy sequences.
• Macros, including syntax quoting and the implicit &form and &env.
• Metadata. (Some collection types don't support it yet.)
• Reference types, including vars, atoms, futures.
• Extensible type system, including defmethod for duck typing. (This is the most significant departure from Clojure.)
• Caching compiler generates real VimL.

VimL interop

• TimL functions are actually VimL dictionaries (objects) containing a dictionary function (method) and a reference to the enclosing scope.
• Defining a symbol baz in namespace foo.bar actually defines g:foo#bar.baz. If that symbol refers to something callable (like a function), calling foo#bar#baz() on the VimL side will invoke it.
• Arbitrary Vim variables and options can be referred to using VimL notation: b:did_ftplugin, v:version, &expandtab. You can also change them with set!: (set! &filetype "timl").
• #*function returns a reference to a built-in or user defined function. You can call it like any other function: (#*toupper "TimL is pretty neat").
• Interact with VimL exceptions with throw/try/catch/finally.
• Call a Vim command with execute: (execute "wq").
• Lisp macros are a wonderful way to encapsulate and hide a lot of the pain points of VimL. The current standard library barely scratches the surface here.

Getting started

If you don't have a preferred installation method, I recommend installing pathogen.vim, and then simply copy and paste:

cd ~/.vim/bundle
git clone git://github.com/tpope/timl.git

Once help tags have been generated, you can view the manual with :help timl. There's not a whole lot there, yet. If you know Clojure, you can probably guess a bunch of the function names.

Start a repl with :TLrepl. Tab complete is your friend. The first time may take several seconds (if your computer is a piece of shit), but compilation is cached, so subsequent invocations will be super quick, even if Vim is restarted.

The familiar ns macro from Clojure is mostly identical in TimL. :refer-clojure is now :refer-timl, which is identical to (refer 'timl.core opts). :use only supports symbol arguments.

(ns my.ns
  (:refer-timl :exclude [+])
  (:use timl.repl)
  (:require [timl.file :as file]
            [timl.test]))

You can use Clojure's in-ns, require, refer, alias, and use, however use and require are limited to a single argument.

(in-ns 'my.ns)
(use 'timl.repl)
(require 'timl.file)
(alias 'file 'timl.file)

Put files in autoload/*.tim in the runtime path and they will be requirable.

License

Copyright © Tim Pope.

The use and distribution terms for this software are covered by the Eclipse Public License 1.0, which can be found in the file epl-v10.html at the root of this distribution.

By using this software in any fashion, you are agreeing to be bound by the terms of this license. You must not remove this notice, or any other, from this software.