TIM Rust library and bindings

This directory contains a Rust library with various helper functions used throughout TIM. Currently, only basic and frequently used functions are defined, but over time the goal is to convert the entire document processing pipeline to use Rust.

The library includes Python bindings, which are used by TIM backend.

Building

To build the library, use ./tim rust command. The command automatically builds and installs the library in the tim_rust/python path.

./tim update all and other commands will automatically invoke the Rust build if necessary.

Quick guide: Defining new functions for Python

tim_rust uses PyO3 to handle interop between Python and Rust.

1. Add the function signature to python/tim_rust.pyi. Define any documentation and type annotations for Python.

   Example:

   def sum(a: int, b: int) -> int:
       """Returns the sum of two integers."""
       ...

   Instead of the method body, use ... to indicate that the function is defined in Rust.

2. Add the function to python/src/lib.rs. Use #[pyfunction] attribute to mark the function as a Python function.

   Example:

   #[pyfunction]
   fn sum(a: i64, b: i64) -> PyResult<i64> {
       Ok(a + b)
   }

   Note that the return type is always PyResult, where T is the actual return type of the function. Refer to PyO3 type conversion chart to see how to convert between Python and Rust types.

3. Add the function to tim_rust module with add_function function in python/src/lib.rs:

   #[pymodule]
   fn tim_rust(_py: Python, m: &PyModule) -> PyResult<()> {
       // Other functions...
       m.add_function(wrap_pyfunction!(sum, m)?)?;
       // Other functions...
       Ok(())
   }