rustleaf 0.1.0

A simple programming language interpreter written in Rust
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37

use crate::core::{RustValue, Value};
use crate::eval::{EvalResult, Evaluator};

#[derive(Debug, Clone)]
pub struct EvalIs {
    pub left: Value,
    pub right: Value,
}

#[crate::rust_value_any]
impl RustValue for EvalIs {
    fn dyn_clone(&self) -> Box<dyn RustValue> {
        Box::new(self.clone())
    }
    fn eval(&self, evaluator: &mut Evaluator) -> anyhow::Result<EvalResult> {
        let left_val = match self.left.eval(evaluator)? {
            Ok(val) => val,
            Err(e) => return Ok(Err(e)),
        };
        let right_val = match self.right.eval(evaluator)? {
            Ok(val) => val,
            Err(e) => return Ok(Err(e)),
        };

        if let Value::RustValue(rust_val_ref) = &right_val {
            if let Ok(result) = rust_val_ref.op_is(&left_val) {
                return Ok(Ok(result));
            }
        }

        Ok(Ok(Value::Bool(left_val == right_val)))
    }

    fn str(&self) -> String {
        format!("{} is {}", self.left.str(), self.right.str())
    }
}