Interface Simplify

interface Simplify {
    rules: SimplifyRule[];
    (expr: string | MathNode): MathNode;
    (
        expr: string | MathNode,
        rules: SimplifyRule[],
        scope?: MathScope<any>,
        options?: SimplifyOptions,
    ): MathNode;
    (
        expr: string | MathNode,
        scope: MathScope,
        options?: SimplifyOptions,
    ): MathNode;
}