bytevm 0.7.1

A tiny bytecode virtual machine
Documentation 
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use bytevm::prelude::*;

#[test]
fn test_fib() {
    
    let input = 5;
    let expected_result = fib(input);

    let mut program  = ProgramBuilder::default();

    program.add_function(FunctionBuilder::default()
        .name("main")
        .arity(0)
        .body(BlockEncoder::default()
            // Declare a local variable to hold the input
            .declare_local("n")
            .push_integer(input)
            .set_local("n")

            // Call the fib function
            .get_local("n")
            .call_function_by_name("fib")

            // Return the result
            .return_value()
        )
        .build()
    );

    program.add_function(FunctionBuilder::default()
        .name("fib")
        .arity(1)
        .body(BlockEncoder::default()
            // Declare local variables for the Fibonacci function
            .declare_local("n")

            // if n <= 1 then return n
            .get_local("n")
            .push_integer(1)
            .less_than_or_equal()
            .jump_if_false("end")
            .get_local("n")
            .return_value()
            .add_label("end")

            // fib(n - 1)
            .get_local("n")
            .push_integer(1)
            .sub()
            .call_function_by_name("fib")

            // fib(n - 2)
            .get_local("n")
            .push_integer(2)
            .sub()
            .call_function_by_name("fib")

            // add the results of fib(n-1) and fib(n-2)
            .add()

            // return the result
            .return_value())
        .build()
    );

    let mut vm = Vm::default();
    vm.load_program(program.build());
    let result = vm.run(None, None).unwrap();

    println!("Time taken: {:?}", result.run_time.as_secs_f64());
    
    assert_eq!(result.result.unwrap(), Variant::Integer(expected_result));
}

fn fib(n: i64) -> i64 {
    if n <= 1 {
        return n;
    }
    fib(n - 1) + fib(n - 2)
}