dellingr 0.4.0

An embeddable, pure-Rust Lua VM with precise instruction-cost accounting
Documentation 
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use dellingr::{ArgCount, RetCount, State};

fn run_boolean(source: &str) -> bool {
    let mut state = State::new();
    state
        .load_string(source)
        .expect("Rust function identity test source compiles");
    state
        .call(ArgCount::Fixed(0), RetCount::Fixed(1))
        .expect("Rust function identity test executes");
    state.to_boolean(-1)
}

#[test]
fn rust_functions_have_value_identity_in_lua() {
    assert!(run_boolean(
        r#"
        local alias = print
        return print == print
            and alias == print
            and rawequal(print, print)
            and print ~= type
        "#,
    ));
}

#[test]
fn rust_functions_work_as_inline_and_promoted_table_keys() {
    assert!(run_boolean(
        r#"
        local inline = {}
        inline[print] = "first"
        inline[print] = "second"

        local promoted = { a = 1, b = 2, c = 3, d = 4 }
        promoted[print] = "first"
        promoted[print] = "second"

        return inline[print] == "second" and promoted[print] == "second"
        "#,
    ));
}

#[test]
fn reassigning_a_rust_function_key_does_not_append_a_duplicate() {
    assert!(run_boolean(
        r#"
        local table = {}
        table[print] = "first"
        table[print] = "second"

        local count = 0
        for key, value in pairs(table) do
            if key == print and value == "second" then
                count = count + 1
            end
        end
        return count == 1
        "#,
    ));
}