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kraken/slj/src/grammar.lalrpop

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use std::str::FromStr;
use std::rc::Rc;
use sl::Form;
grammar;
pub Term: Rc<Form> = {
"true" => Form::new_bool(true),
"false" => Form::new_bool(false),
NUM => Form::new_int(i32::from_str(<>).unwrap()),
SYM => Rc::new(Form::Symbol(<>.to_owned())),
"(" <ListInside?> ")" => <>.unwrap_or(Form::new_nil()),
"'" <Term> => Rc::new(Form::Pair(Rc::new(Form::Symbol("quote".to_owned())), Rc::new(Form::Pair(<>, Form::new_nil())))),
"!" <h: Term> <t: Term> => {
h.append(t).unwrap()
},
};
ListInside: Rc<Form> = {
<Term> => Rc::new(Form::Pair(<>, Form::new_nil())),
<h: Term> <t: ListInside> => Rc::new(Form::Pair(h, t)),
<a: Term> "." <d: Term> => Rc::new(Form::Pair(a, d)),
}
match {
"true",
"false",
"(",
")",
".",
"'",
"!",
r"[0-9]+" => NUM,
r"[a-zA-Z+*/_=?%&|^<>-][\w+*/=_?%&|^<>-]*" => SYM,
r"(;[^\n]*\n)|\s+" => { }
}