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use std::fmt::{self, Display};
#[derive(Debug, PartialEq, Clone)]
pub enum Value {
Num(i32),
Bool(bool),
Sym(String),
App(Box<Value>, Box<Value>),
Lam(String, Box<Value>),
Def(String, Box<Value>),
}
impl Display for Value {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
match self {
Value::Num(i) => write!(f, "{}", i),
Value::Bool(b) => write!(f, "{}", b),
Value::Sym(s) => write!(f, "{}", s),
Value::App(l, r) => write!(f, "({} {})", l, r),
Value::Lam(var, body) => write!(f, "(lam {} {})", var, body),
Value::Def(var, value) => write!(f, "(def {} {})", var, value),
}
}
}
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