Simple typings for the node-rules package (https://github.com/mithunsatheesh/node-rules)

node-rules.d.ts

declare module 'node-rules' {
  export default class RuleEngine {
    constructor(rules?: Rule[] | Rule, options?: object);
    register(rule: Rule): any;
    sync(): Rule[] | void;
    execute(fact: {[x: string]: any}, cb: (data: {result?: any, reason?: any, [x: string]: any}) => void): void;
    findRules(filter?: any): Rule[] | void;
    turn(state: string, filter: any): Rule[] | void;
    prioritize(priority: number, filter: any): Rule[] | void;
    toJSON(): string;
    fromJSON(rules: string): any;
    rule(): Rule | void;
    when(condition: any): void;
    restart(): any;
    stop(): void;
    next(): any;
  }

  export interface Rule {
    name: string;
    priority?: number;
    condition: (R: RuleEngine) => void;
    consequence: (R: RuleEngine) => void;
  }
}