import stringify = require("csv-stringify"); stringify([["1", "2", "3"], ["4", "5", "6"]], (error: Error, output: string): void => { // nothing }); stringify([["1", "2", "3"], ["4", "5", "6"]], { delimiter: "," }, (error: Error, output: string): void => { // nothing }); var s = stringify({ delimiter: "," }); s.write(["1", "2", "3"]);