import { Expression } from './Expression';
export declare enum ConstantExpressionType {
    Object = -2,
    Array = -1,
    Null = 0,
    Boolean = 1,
    Number = 2,
    String = 3,
    Date = 4
}
export interface ConstantExpression extends Expression {
    value: unknown;
    type: ConstantExpressionType;
}
declare const NullExpression: ConstantExpression;
export { NullExpression };