declare namespace nasl.langUtil {
    export class Collection<Arr extends Array<any>> {
        // name = 'Collection';
        FROM<T extends Array<any>>(collection: Collection<T>): Collection<T>;
        INNER_JOIN<K extends Array<any>>(collection: Collection<K>): Collection<[...Arr, ...K]>;
        LEFT_JOIN<K extends Array<any>>(collection: Collection<K>): Collection<[...Arr, ...K]>;
        RIGHT_JOIN<K extends Array<any>>(collection: Collection<K>): Collection<[...Arr, ...K]>;
        OUTER_JOIN<K extends Array<any>>(collection: Collection<K>): Collection<[...Arr, ...K]>;

        ON(expr: (...types: Arr) => nasl.core.Boolean): Collection<Arr>;
        WHERE(...exprs: Array<(...types: Arr) => nasl.core.Boolean>): Collection<Arr>;
        WHEREPLAYGROUND(...exprs: Array<(...types: Arr) => nasl.core.Any>): Collection<Arr>;
        GROUP_BY(...exprs: Array<(...types: Arr) => any>): Collection<Arr>;
        SELECT(...exprs: Array<(...types: Arr) => any>): Collection<Arr>;
        HAVING(...exprs: Array<(...types: Arr) => nasl.core.Boolean>): Collection<Arr>;
        HAVINGPLAYGROUND(...exprs: Array<(...types: Arr) => nasl.core.Any>): Collection<Arr>;
        ORDER_BY(...exprs: Array<(...types: Arr) => any>): Collection<Arr>;
        LIMIT(expr: (...types: Arr) => any): Collection<Arr>;
        // PAGINATE(page: nasl.core.Long, size: nasl.core.Long): Collection<Arr>
        // SELECT_PAGE_OF<R>(expr: (...types: Arr) => R): <R>
    }

    export function FROM<T extends Array<any>>(collection: Collection<T>): Collection<T>;
    export function STARTWITH(str1: nasl.core.String, str2: nasl.core.String): nasl.core.Boolean;
    export function ENDWITH(str1: nasl.core.String, str2: nasl.core.String): nasl.core.Boolean;
    export function LIKE(str1: nasl.core.String, str2: nasl.core.String): nasl.core.Boolean;
    export function IN<T>(value: T, list: nasl.collection.List<T>): nasl.core.Boolean;
    export function ISNULL(value: any): nasl.core.Boolean;
    export function NOT(value: nasl.core.Boolean): nasl.core.Boolean;
    export function COUNT(value: any): nasl.core.Long;
    export function COUNTD(value: any): nasl.core.Long;
    export function SUM<T extends nasl.core.Long | nasl.core.Decimal>(value: T): T;
    export function AVG<T extends nasl.core.Long | nasl.core.Decimal>(value: T): nasl.core.Decimal;
    export function MAX<T extends nasl.core.Long | nasl.core.Decimal | nasl.core.Boolean | nasl.core.String | nasl.core.Date | nasl.core.Time | nasl.core.DateTime>(value: T): T;
    export function MIN<T extends nasl.core.Long | nasl.core.Decimal | nasl.core.Boolean | nasl.core.String | nasl.core.Date | nasl.core.Time | nasl.core.DateTime>(value: T): T;

    export function ruleIn<T>(value: T, list: T): nasl.core.Boolean;
    // export function CONCAT(a: nasl.core.String, b: nasl.core.String): boolean
}


// namespace app.dataSources.defaultDS.entities {
// }
// nasl.langUtil.FROM(new nasl.langUtil.Collection<[app.dataSources.defaultDS.entities.Student]>()
//     .LEFT_JOIN(new nasl.langUtil.Collection<[app.dataSources.defaultDS.entities.School]>())
//     .ON((Student, School) => Student.schoolId === School.id))
//     .WHERE((Student, School) => Student.age > new nasl.core.Long(200))
//     .ORDER_BY((Student, School) => Student.name, 'ASC')
//     .SELECT((Student, School) => ({ Student, School }))