It's an experimental emulator of a machine that understands 𝜑-calculus expressions, which is the formalism behind EO programming language.

To build it, install Rust and then:

$ cargo build --release

If everything goes well, an executable binary will be in target/release/fibonacci:

$ target/release/fibonacci 7 40

This will calculate the 7th Fibonacci number 40 times. Don't try to play with much larger numbers, this binary code is very slow. It's just an experiment.

To compile your own program instead of this primitive recursive Fibonacci calculator, you have to convert EO code into 𝜑-calculus expressions and then pass them to Emu struct like this:

use phie::emu::Emu;
pub fn main() {
    let mut emu: Emu = "
        ν0(𝜋) ↦ ⟦ 𝜑 ↦ ν3(𝜋) ⟧
        ν1(𝜋) ↦ ⟦ Δ ↦ 0x002A ⟧
        ν2(𝜋) ↦ ⟦ λ ↦ int-add, ρ ↦ 𝜋.𝛼0, 𝛼0 ↦ 𝜋.𝛼1 ⟧
        ν3(𝜋) ↦ ⟦ 𝜑 ↦ ν2(ξ), 𝛼0 ↦ ν1(𝜋), 𝛼1 ↦ ν1(𝜋) ⟧
    ".parse().unwrap();
    let dtz = emu.dataize();
    print!("The result is: {}", dtz.0);
}

This code is equivalent to the following EO code:

[] > foo
  42 > x
  x.add x > @

But in a more "functional" way:

[] > foo
  42 > x
  int-add > @
    x
    x

More tests are in src/emu.rs file.

How to Contribute

First, install Rust and then:

$ cargo test -vv --release

If everything goes well, an executable binary will be in target/release/phie:

$ target/release/phie --help

Then, fork repository, make changes, send us a pull request. We will review your changes and apply them to the master branch shortly, provided they don't violate our quality standards. To avoid frustration, before sending us your pull request please run cargo test again. Also, run cargo fmt and cargo clippy.