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export as_prec;
export unop_prec;
export token_to_binop;
import token::*;
import token::token;
import ast::*;
/// Unary operators have higher precedence than binary
const unop_prec: uint = 100u;
/**
* Precedence of the `as` operator, which is a binary operator
* but is not represented in the precedence table.
*/
const as_prec: uint = 11u;
/**
* Maps a token to a record specifying the corresponding binary
* operator and its precedence
*/
fn token_to_binop(tok: token) -> option<ast::binop> {
match tok {
BINOP(STAR) => some(mul),
BINOP(SLASH) => some(div),
BINOP(PERCENT) => some(rem),
// 'as' sits between here with 11
BINOP(PLUS) => some(add),
BINOP(MINUS) => some(subtract),
BINOP(SHL) => some(shl),
BINOP(SHR) => some(shr),
BINOP(AND) => some(bitand),
BINOP(CARET) => some(bitxor),
BINOP(OR) => some(bitor),
LT => some(lt),
LE => some(le),
GE => some(ge),
GT => some(gt),
EQEQ => some(eq),
NE => some(ne),
ANDAND => some(and),
OROR => some(or),
_ => none
}
}
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