egg: egraphs good

Developing

It's written in Rust. Typically, you install Rust using rustup.

Run cargo doc --open to build and open the documentation in a browser.

Before committing/pushing, make sure to run ./check.sh, which runs all the tests and lints that Travis will.

Tests

Running cargo tests will run the tests.

There are a couple interesting tests in the tests directory:

• prop.rs implements propositional logic and proves some simple theorems.
• math.rs implements real arithmetic, with rewrite rules and a test case taken from Herbie.