OCaml-gen

This crate provides automatic generation of OCaml bindings. Refer to the rustdoc for more information.

Binding generation

Here's an example of generating some bindings:

```rust // initialize your environment let env = &mut Env::default();

// choose where you want to write the bindings let w = &mut std::io::stdout();

// we need to create fake generic placeholders for generic structs declfakegeneric!(T1, 0); declfakegeneric!(T2, 1);

// you can declare modules decl_module!(w, env, "Types", {

// and types
decl_type!(w, env, SomeType);

// and even generic types
decl_type!(w, env, SomeGenericType::<T1>);

// you can also rename a type
decl_type!(w, env, SomeOtherGenericType::<T1> => "thing");

});

decl_module!(w, env, "ImportantType", {

// the OCaml way is often to rename your module's main type as `t`
decl_type!(w, env, CamlBigInteger256 => "t");

// you can declare functions as well
// note that the underlying function calls `caml_of_numeral_to_ocaml`
// so you have to either import all (e.g. `use path::*`)
// or you have to import `caml_of_numeral_to_ocaml`
decl_func!(w, env, caml_of_numeral => "of_numeral");

}); ```

Binding description

To allow the previous example to work, you must derive the correct functions on your types and functions. To do that, you can use the ocaml-gen-derive crate.

To allow generation of bindings on structs, use Struct:

```rust

[ocaml_gen::Struct]

struct MyType { // ... } ```

To allow generation of bindings on enums, use ocaml_gen::Enum:

```rust

[ocaml_gen::Enum]

enum MyType { // ... } ```

To allow generation of bindings on functions, use ocaml_gen::func:

```rust

[ocaml_gen::func]

[ocaml::func] // if you use the crate ocaml-rs' macro, it must appear after

pub fn your_function(arg1: String) { //... } ```

To allow generation of bindings on custom types, use ocaml_gen::CustomType:

```rust

[ocaml_gen::CustomType]

struct MyCustomType { // ... } ```

Organization

• ocaml-gen: the tool that allows us to generate the OCaml bindings from the Rust code.
• ocaml-gen-derive: derive macros have to be a in separate crate, so they are here. This crate is re-exported by ocaml-gen so end users should not have to worry about it.
• tests/: contains some tests. If you are looking for examples on how to use ocaml-gen, you can check that folder.

Additional resources

you can check the recording I made when I first introduced the tool internally.