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use std::fmt;
use crate::sexp::{SLeaf, SExp, SLeaf::*, SExp::*, util::*};
impl fmt::Display for SLeaf {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
write!(f, "{}", match self {
Add => "+".to_string(),
Sub => "-".to_string(),
Mul => "*".to_string(),
Div => "/".to_string(),
Int(x) => x.to_string(),
Var(s) => s.to_string(),
Quote => "quote".to_string(),
Nil => "()".to_string(),
})
}
}
impl fmt::Display for SExp {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
match self {
Atom(leaf) => write!(f, "{}", leaf.to_string()),
SCons(a, b) => {
match scons(a.clone(), b.clone()).into_vec() {
Ok(l) => write!(
f,
"({})",
l.into_iter()
.map(|x| x.to_string())
.collect::<Vec<String>>()
.join(" ")
),
Err(_) => write!(f, "({} {})", *a, *b),
}
}
}
}
}
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