There are currently two active BQN implementations: the self-hosted one in this repository, and the independent dzaima/BQN. Neither is entirely complete but they are quite capable for pure programming tasks (say, implementing a compiler). dzaima/BQN has good performance while self-hosted is a few hundred times slower. I tend to develop parts of applications in the online REPL and move to dzaima/BQN scripts in order to run them.
See the subsections below for instructions on specific implementations.
This version of BQN is implemented mainly in BQN itself, but a host language supplies basic functionality and can also replace primitives for better performance. This also allows embedding, where programs in the host language can include BQN code. It fully supports all primitives except a few cases of structural Under (⌾), but is still missing some advanced features: block headers and multiple body syntax, derived 1-modifiers, and block returns.
Support in the following languages has been implemented:
The online REPL is here. The file docs/bqn.js is zero-dependency Javascript, and can be loaded from HTML or Node.js. For command line use, call the Node.js script bqn.js, passing a file and •args, or -e to execute all remaining arguments directly and print the results. This notebook shows how to run it in an Observable notebook.
C sources are kept in the CBQN repository, but they also require the self-hosted bytecode to be built using cc.bqn in that repository. Although cc.bqn is typically run with dzaima/BQN, this can be changed by modifying the #! line at the beginning, or linking dbqn to a different executable. To use only the BQN and CBQN repositories, avoiding dzaima/BQN, first build with bqn.js—this is slow, but should take under a minute even on low-end hardware—then switch to CBQN itself afterwards for faster builds.
dzaima/BQN is an implementation in Java created by modifying the existing dzaima/APL. It should be easy to run on desktop Linux and Android. It is still in development and has almost complete syntax support but incomplete primitive support: major missing functionality is dyadic Depth (⚇), Windows (↕), and many cases of set functions (⊐⊒∊⍷, mostly with rank >1).
In this repository and elsewhere, dzaima/BQN scripts are called with #! /usr/bin/env dbqn. This requires an executable file dbqn somewhere in your path with the following contents:
#! /bin/bash java -jar /path/to/dzaima/BQN/BQN.jar "$@"
If compiled with Native Image, nBQN can be used directly instead.
This repository contains a dzaima/BQN script dzref that fills in gaps in primitive support with BQN implementations. dzaima/BQN has good enough primitive support that I now almost never use this, but it's still needed for the website generator md.bqn. The command-line arguments are a script to run and followed by the •args to supply to it.
BQN2NGN is a prototype implementation in Javascript build to experiment with the langauge, which is now abandoned.