rustleaf 0.1.0

A simple programming language interpreter written in Rust
Documentation 
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use crate::core::{RustValue, Value};
use crate::eval::{ControlFlow, ErrorKind, EvalResult, Evaluator};
use anyhow::anyhow;

#[derive(Debug, Clone)]
pub struct EvalAssign {
    pub name: String,
    pub expr: Value,
}

#[crate::rust_value_any]
impl RustValue for EvalAssign {
    fn dyn_clone(&self) -> Box<dyn RustValue> {
        Box::new(self.clone())
    }

    fn eval(&self, evaluator: &mut Evaluator) -> anyhow::Result<EvalResult> {
        let value = match self.expr.eval(evaluator)? {
            Ok(val) => val,
            Err(e) => return Ok(Err(e)),
        };
        match evaluator.current_env.set(&self.name, value) {
            Ok(_) => Ok(Ok(Value::Unit)),
            Err(err) => Ok(Err(ControlFlow::Error(ErrorKind::SystemError(anyhow!(
                err
            ))))),
        }
    }

    fn str(&self) -> String {
        format!("{} = {}", self.name, self.expr.str())
    }
}