PiLisp

PiLisp—An interpreted Lisp inspired by Clojure, implemented in Dart.

The language implemented in pilisp-core runs on all targets that Dart supports.

Appetizer

(println "Hello world!")
;; (STDOUT) "Hello world!\n"
;;=> nil

(reduce + (range 5))
;;=> 10

(pl> bindings | keys | sort | drop 900 | take 10)
;;=>
;; [
;;   stringify-keys
;;   subs
;;   substring
;;   swap!
;;   symbol
;;   symbol?
;;   take
;;   take-while
;;   tenth
;;   term
;; ]

(dart/int.tryParse "1234567891234567891")
;;=> 1234567891234567891

(dart/int.tryParse "12345678912345678912")
;;=> nil

(dart/BigInt.tryParse "123456789123456789123456789")
;;=> 123456789123456789123456789

(count (apropos-full "dart/"))
;;=> 613

(map str/upper-case ["no" "lazy" "seqs"])
;;=>
;; [
;;   "NO"
;;   "LAZY"
;;   "SEQS"
;; ]

Peruse the Tour for a more detailed walk-through.

How to Learn

Check out:

• Installation
• REPL Usage
• CLI Commands

Motivation

PiLisp is written in Dart to allow for (1) leveraging Dart libraries while (2) running on all the targets that the Dart platform supports, but especially being able to (3) compile programs to standalone native executables.

PiLisp is a Lisp modeled after Clojure, because I've used Clojure for years and find it to be an elegant instrument of thought and computation.

In 2022, I wrote a program to interact with Shortcut's REST API from the CLI called sc and cursed it with an intentionally crippled Lisp implementation. The hallmark that Lisp's design was making parentheses optional for top-level invocation and supporting the pipe | character as an infix thread-first operator.

PiLisp is a shortened form of "Piped Lisp," because I set out to reimplement that underpowered Lisp with a proper approach, knowing that I could support its piping/expression-threading behavior via a macro, rather than by hard-coding it into the language implementation. As projects tend to do, PiLisp morphed from being a language that I intended to re-embed into the sc project into an independent language with interesting features in its own right. It became so far removed from the original project that it was not longer straightforward to drop it in as a replacement.