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use std::fmt::Display;
use crate::lex::token::Token;
#[derive(Debug)]
pub enum Expression {
Binary {
left: Box<Expression>,
op: Token,
right: Box<Expression>,
},
Unary {
op: Token,
right: Box<Expression>,
},
Group(Box<Expression>),
Literal(Token),
}
impl Display for Expression {
fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
self.nested_fmt(f, 0)
}
}
impl Expression {
fn nested_fmt(&self, f: &mut std::fmt::Formatter<'_>, depth: usize) -> std::fmt::Result {
let pad = " ".repeat(depth);
match self {
Expression::Binary { left, op, right } => {
writeln!(f, "{}Binary:", pad)?;
writeln!(f, "{}- Left:", pad)?;
left.nested_fmt(f, depth + 1)?;
writeln!(f, "{}- Operator: {:?}", pad, op.variant)?;
writeln!(f, "{}- Right:", pad)?;
right.nested_fmt(f, depth + 1)?;
}
Expression::Unary { op, right } => {
writeln!(f, "{}Unary:", pad)?;
writeln!(f, "{}- Operator: {:?}", pad, op.variant)?;
writeln!(f, "{}- Right:", pad)?;
right.nested_fmt(f, depth + 1)?;
}
Expression::Group(node) => {
writeln!(f, "{}Group:", pad)?;
node.nested_fmt(f, depth + 1)?;
}
Expression::Literal(token) => {
writeln!(f, "{}Literal: {:?}", pad, token.variant)?;
}
}
Ok(())
}
}
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