import { VELOCITY_AST } from '../type';
import { Compile } from './base-compile';
/**
 * expression support, include math, logic, compare expression
 */
export declare class Expression extends Compile {
    /**
     * Expression evaluation, mainly for mathematical expressions, logical operations and comparison operations.
     * For basic data types at the lowest level, getLiteral is used for evaluation.
     * When getLiteral encounters references, getReferences is used for evaluation.
     */
    getExpression(ast: VELOCITY_AST): any;
}