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use std::fmt;
use number::LispNumber;
mod error;
mod lex;
mod number;
#[derive(Debug, PartialEq)]
pub enum LispExpr {
Number(LispNumber),
List(Vec<LispExpr>),
StringLit(String),
BoolLit(bool),
Ident(String),
Function(LispFunction),
}
impl fmt::Display for LispExpr {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
match self {
LispExpr::Number(n) => write!(f, "{}", n)?,
LispExpr::List(l) => {
for expr in l.iter() {
write!(f, " {} ", expr)?
}
}
LispExpr::StringLit(s) => write!(f, "{:?}", s)?,
LispExpr::BoolLit(b) => {
if *b {
write!(f, "#t")?
} else {
write!(f, "#f")?
}
}
LispExpr::Ident(s) => write!(f, "{}", s)?,
LispExpr::Function(_) => write!(f, "<#procedure>")?,
};
Ok(())
}
}
pub type Environment = Vec<(String, LispExpr)>;
#[derive(Debug, PartialEq)]
struct LispFunction {}
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