interface Array { indexOfField : (propertyName: string, value: any) => number; } declare module 'lodash.assign' { import {assign} from 'lodash'; export = assign; } declare module 'lodash.isobject' { import {isObject} from 'lodash'; export = isObject; } declare module 'lodash.isstring' { import {isString} from 'lodash'; export = isString; } declare module 'backo2';