Generative Expressions

Generative Expressions (Geex) is a code generation tool for writing high-level Clojure code that generates fast low-level code.

About the state of this library

This library is currently quite unstable and is lacking in some areas, notably:

• Documentation
• Testing
• Cleanliness of the code
• Lack of some basic features

All these points are currently top priorities for this library.

Getting started

Geex can be obtained as a Maven dependency, so in your Leiningen project, you just have to add the line

[geex "0.4.1"]

You can also try it out by cloning this repository and looking at the examples, such as

• How to compute the square root using Newton-Raphson
• Forward-mode automatic differentiation
• Circle fitting
• Expression templates on vectors à la C++
• More matrix operations (without expression templates).

Benchmarks

Have been done, will be published.

Usage

TODO: Would be nice to have.

See the examples under the Getting started section.

API Reference

The documentation can be generated using lein codox.

Use the ^:no-doc on symbols that should be excluded https://github.com/weavejester/codox#metadata-options

Module structure

If you add [lein-ns-dep-graph "0.2.0-SNAPSHOT"] to your Leiningen plugins, this graph can be generated using lein ns-dep-graph:

geex.core contains the core components of code generation and analysis.

geex.common is a library of common operations.

geex.java contains specific support for the Java platform.

Issues and features to address

Important or easy to implement:

• Neat way of saving Java to disk or loading it directly with Janino (environment variable switch or something).
• Protect EBMD-functions against nil. They create horrible stack traces now.
• Make sure that geex.common/check works (I think it does).
• String concatenation
• nth to access chars only works with integer seeds.
• Check arity when calling Java operators
• Copy extra examples from other code (router, cljd)
• Make generated code formatting optional.

Less important:

• Strip away operations without sideeffects if they are not needed.
• Unite identical pure operations.

Contributions

You can contribute by filing bug issues. Fixing minor issues such as failing builds for different platforms is also important.

License

Copyright © 2019 Jonas Östlund

Distributed under the Eclipse Public License either version 1.0 or (at your option) any later version.