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use std::str::FromStr;
use ast::{self, WithLocation};
grammar;
pub Program: ast::Program = {
Expression => ast::Program(<>),
};
Expression: Box<ast::WithLocation<ast::Expression>> = {
<e1:Expression> "+" <e2:ExpressionMul> => Box::new(e1.join_map(*e2, |v1, v2| {
ast::Expression::BinOp(ast::BinOp::Add, Box::new(v1), Box::new(v2))
})),
<e1:Expression> "-" <e2:ExpressionMul> => Box::new(e1.join_map(*e2, |v1, v2| {
ast::Expression::BinOp(ast::BinOp::Sub, Box::new(v1), Box::new(v2))
})),
<ExpressionMul> => <>,
};
ExpressionMul: Box<ast::WithLocation<ast::Expression>> = {
<e1:ExpressionMul> "*" <e2:ExpressionSign> => Box::new(e1.join_map(*e2, |v1, v2| {
ast::Expression::BinOp(ast::BinOp::Mul, Box::new(v1), Box::new(v2))
})),
<e1:ExpressionMul> "/" <e2:ExpressionSign> => Box::new(e1.join_map(*e2, |v1, v2| {
ast::Expression::BinOp(ast::BinOp::Div, Box::new(v1), Box::new(v2))
})),
<e1:ExpressionMul> "//" <e2:ExpressionSign> => Box::new(e1.join_map(*e2, |v1, v2| {
ast::Expression::BinOp(ast::BinOp::FloorDiv, Box::new(v1), Box::new(v2))
})),
<ExpressionSign> => <>,
};
ExpressionSign: Box<ast::WithLocation<ast::Expression>> = {
<l: @L> "+" <e: ExpressionBase> <r: @R> => Box::new(WithLocation::new(
ast::Expression::UnaryOp(ast::UnaryOp::Pos, e),
l, r
)),
<l: @L> "-" <e: ExpressionBase> <r: @R> => Box::new(WithLocation::new(
ast::Expression::UnaryOp(ast::UnaryOp::Neg, e),
l, r
)),
<ExpressionBase> => <>,
};
ExpressionBase: Box<ast::WithLocation<ast::Expression>> = {
Num => Box::new(<>.map(|v| ast::Expression::Number(v))),
Spanned<r"nil"> => Box::new(<>.map(|v| ast::Expression::Nil)),
"(" <Expression> ")" => <>,
};
Num: WithLocation<u64> = <e: Spanned<r"[0-9]+">> => e.map(|v| u64::from_str(v).unwrap());
Spanned<T>: WithLocation<T> = {
<l: @L> <v: T> <r: @R> => WithLocation::new(v, l, r)
};
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