Hello and welcome to Nu.

I created Nu because I wanted a better way to write software.

I wanted to write with a language as flexible and powerful as Lisp, but I also wanted to be able to work with the many libraries and high-performance subsystems written in C, including the ones that I write myself. So a tight integration with C was my highest priority; that ruled and drove the implementation of Nu. That's why Nu is "C over lambda."

It is easier to integrate with C when you have a disciplined way of structuring C code. Popular scripting languages (Python, Ruby, Lua, etc.) make many implementation-dependent impositions on the C code that they call. Their artifacts are often called "glue code" and are usually ugly, cumbersome, and unpleasant to generate.

Objective-C provides a proven way of structuring C code that has no scripting language implementation dependencies. But it can do much more than that. Objective-C can also serve as a platform for a powerful dynamic language.
Nu was designed to take full advantage of that. It was also designed to provide many of the elements of successful scripting languages, notably Ruby, while adding the syntactic simplicity and flexibility of Lisp.

Nu is copyrighted open-source software that is released under the Apache License, version 2.0. For details on the license, see the LICENSE file. In its use to name a programming language, "Nu" is a trademark of Radtastical Inc.

These are the instructions for installing Nu on a Macintosh or Linux system. Linux builds require several additional dependencies. The included ubuntu.sh script can be used to install these dependencies on a system running Ubuntu 18.04 (and possibly other versions). Installation instructions for some other UNIX-based operating systems (Debian, OpenSolaris, and FreeBSD) are in notes/OBSOLETE and will probably not work without modifications. Macintosh and Ubuntu builds are verified with Travis.

If you've installed Nu previously using a package manager (e.g. Fink, MacPorts), start by using the package manager to uninstall the old version.

1. Use make to build mininush, a minimal version of the Nu shell.

$ make

2. Now use mininush to run nuke to complete the Nu build process. This builds Nu.framework and nush, the Nu shell.

$ ./mininush tools/nuke

3. Use mininush again to install Nu, nush, and the Nu tools.

$ ./mininush tools/nuke install

Since the copying step uses sudo, you will be prompted for your password.

4. Test your installation.

$ nuke test

From now on, you can use the installed nush to run nuke. To see for yourself, rebuild everything from scratch:

$ nuke clobber
$ nuke
$ nuke install

See the Nukefile for other useful tasks.

On Macintosh systems, Nu requires Mac OS X version 10.5 or greater. It is also possible to build Nu to run on Linux systems and the Apple iPhone.

• notes/DEMO contains a simple tutorial exercise that can acquaint you with Nu.
• notes/USAGE describes a few of the ways that you can use Nu.
• notes/ERRORS contains some pitfalls that I've encountered when programming with Nu.
• notes/TODO contains some open issues that I'd like to address in Nu.
• The examples directory contains several fun and interesting examples.

Tim Burks ([email protected])
Los Altos, California, USA