Question 1

How do I expose a Rust function to Lua using hlua?

Accepted Answer

Wrap your Rust function with hlua::functionX where X is the number of parameters, then use lua.set to add it as a global variable. For example, hlua::function2(add) exposes a two-parameter function, and Lua can call it directly.

Question 2

hlua vs rlua: which should I use for embedding Lua in Rust?

Accepted Answer

hlua focuses on high-level safety and ease of use for Lua 5.2, while rlua often supports newer Lua versions and might offer different trade-offs. Choose hlua if you prioritize a straightforward API and Lua 5.2 compatibility; consider rlua for Lua 5.3+ features or different design goals.

Question 3

Can I use hlua with LuaJIT?

Accepted Answer

hlua is designed for Lua 5.2, so it may not be compatible with LuaJIT which is based on Lua 5.1. You might need to look for alternative bindings or forks if LuaJIT support is required for your project.

Question 4

How to handle errors when executing Lua code in hlua?

Accepted Answer

The execute method returns a Result<T, ExecutionError>, so use Rust's error handling like unwrap or match. If a Rust function returns a Result with an error, it triggers a Lua error, allowing integrated error propagation between Rust and Lua.

Question 5

Is hlua thread-safe for concurrent Lua contexts?

Accepted Answer

The Lua struct requires mutable access and holds references, so sharing across threads is challenging without synchronization. Typically, you manage separate Lua contexts per thread or use Rust's concurrency primitives to ensure safety, as enforced by the ownership model.

Question 6

How to read a Lua table into a Rust HashMap with hlua?

Accepted Answer

Use lua.get to read into a HashMap<AnyHashableLuaValue, AnyLuaValue>, as shown in the README. Ensure the table keys are hashable, and handle conversions; for example, Lua tables with mixed keys can be read directly into HashMaps.

hlua

What is hlua?

Overview

Use Cases

Best For

Related Projects

Found a gem we're missing?

Not Ideal For

Pros & Cons

Pros

Cons

Frequently Asked Questions