Macro minutus::define_funcall

define_funcall!() { /* proc-macro */ }

Define methods for MrbValue.

Examples

minutus::define_funcall! {
    fn inspect(self) -> String;
    fn concat(self, other: Vec<&str>) -> Vec<String> => "+";
}

fn main() {
    let runtime = minutus::Evaluator::build();
    let mruby_array: minutus::types::MrbValue = runtime.evaluate("['aaa', 'bbb']").unwrap();
    assert_eq!("[\"aaa\", \"bbb\"]", mruby_array.inspect().unwrap());
    assert_eq!(vec![String::from("aaa"), String::from("bbb"), String::from("ccc")], mruby_array.concat(vec!["ccc"]).unwrap());
}

By giving target type for define_funcall!, methods are defined only on given type.

use minutus::mruby::*;
use minutus::types::*;
use minutus::*;

struct CustomNumeric(MrbValue);
impl MrbValueLike for CustomNumeric {
    fn mrb(&self) -> *mut minu_state {
        self.0.mrb()
    }

    fn val(&self) -> minu_value {
        self.0.val()
    }
}
impl TryFromMrb for CustomNumeric {
    fn try_from_mrb(value: MrbValue) -> MrbResult<Self> {
        // You should check the value in reality!
        Ok(CustomNumeric(value))
    }
}
impl TryIntoMrb for CustomNumeric {
    fn try_into_mrb(self, _mrb: *mut minu_state) -> MrbResult<MrbValue> {
        Ok(self.0)
    }
}

// MrbValueLike, TryFromMrb and TryIntoMrb must be implemeted for CustomNumeric
define_funcall! {
  CustomNumeric;
  fn plus(&self, other: CustomNumeric) -> CustomNumeric => "+";
  fn inspect(&self) -> String;
}

fn main() {
    let runtime = Evaluator::build();
    let num_1 = runtime.eval_to::<CustomNumeric>("123").unwrap();
    let num_2 = runtime.eval_to::<CustomNumeric>("246").unwrap();
    let result = num_1.plus(num_2).unwrap().inspect().unwrap();
    assert_eq!("369", result);

    let mrb_value = runtime.evaluate("111").unwrap();
    // This does not compile.
    // mrb_value.plus(num_2)
}