UNPKG

mingo

Version:

MongoDB query language for in-memory objects

17 lines (16 loc) 566 B
import { evalExpr } from "../../core/_internal"; import { isInteger } from "../../util"; import { errExpectNumber, INT_OPTS } from "../expression/_internal"; import { $push } from "./push"; const $firstN = (coll, expr, options) => { const foe = options.failOnError; const copts = options; const m = coll.length; const n = evalExpr(copts?.local?.groupId, expr.n, copts); if (!isInteger(n) || n < 1) return errExpectNumber(foe, "$firstN 'n'", INT_OPTS.pos); return $push(m <= n ? coll : coll.slice(0, n), expr.input, options); }; export { $firstN };