import { ExprElement, ExprIdentifier, ExprNumber, ExprOperator, ExprSpace, ExprString } from './elements';
export declare function tokenize(str: string): (ExprNumber | ExprString | ExprSpace | ExprIdentifier | ExprOperator)[];
export declare function matchBrackets(tokens: ExprElement[], context?: {
    variables?: string[];
}): ExprElement;
export declare function collapseTerm(tokens: ExprElement[]): ExprElement;