diff --git a/packages/xlsx-cli/index.js b/packages/xlsx-cli/index.js
index d64852e..6719ea2 100644
--- a/packages/xlsx-cli/index.js
+++ b/packages/xlsx-cli/index.js
@@ -1,304 +1,306 @@
-#!/usr/bin/env node
-/* index.js (C) 2020-present  SheetJS -- http://sheetjs.com */
-/* eslint-env node */
-/* vim: set ts=2 ft=javascript: */
-
-var n = "xlsx-cli";
-var X = require('xlsx');
-require('exit-on-epipe');
-var fs = require('fs'), program = require('commander');
-function run() {
-  program
-    .version(X.version)
-    .usage('[options] <file> [sheetname]')
-    .option('-f, --file <file>', 'use specified workbook')
-    .option('-s, --sheet <sheet>', 'print specified sheet (default first sheet)')
-    .option('-N, --sheet-index <idx>', 'use specified sheet index (0-based)')
-    .option('-p, --password <pw>', 'if file is encrypted, try with specified pw')
-    .option('-l, --list-sheets', 'list sheet names and exit')
-    .option('-o, --output <file>', 'output to specified file')
-
-    .option('-B, --xlsb', 'emit XLSB to <sheetname> or <file>.xlsb')
-    .option('-M, --xlsm', 'emit XLSM to <sheetname> or <file>.xlsm')
-    .option('-X, --xlsx', 'emit XLSX to <sheetname> or <file>.xlsx')
-    .option('-I, --xlam', 'emit XLAM to <sheetname> or <file>.xlam')
-    .option('-Y, --ods', 'emit ODS  to <sheetname> or <file>.ods')
-    .option('-8, --xls', 'emit XLS  to <sheetname> or <file>.xls (BIFF8)')
-    .option('-5, --biff5', 'emit XLS  to <sheetname> or <file>.xls (BIFF5)')
-    .option('-4, --biff4', 'emit XLS  to <sheetname> or <file>.xls (BIFF4)')
-    .option('-3, --biff3', 'emit XLS  to <sheetname> or <file>.xls (BIFF3)')
-    .option('-2, --biff2', 'emit XLS  to <sheetname> or <file>.xls (BIFF2)')
-    .option('-i, --xla', 'emit XLA to <sheetname> or <file>.xla')
-    .option('-6, --xlml', 'emit SSML to <sheetname> or <file>.xls (2003 XML)')
-    .option('-T, --fods', 'emit FODS to <sheetname> or <file>.fods (Flat ODS)')
-    .option('--wk3', 'emit WK3  to <sheetname> or <file>.txt (Lotus WK3)')
-    .option('--numbers', 'emit NUMBERS to <sheetname> or <file>.numbers')
-
-    .option('-S, --formulae', 'emit list of values and formulae')
-    .option('-j, --json', 'emit formatted JSON (all fields text)')
-    .option('-J, --raw-js', 'emit raw JS object (raw numbers)')
-    .option('-A, --arrays', 'emit rows as JS objects (raw numbers)')
-    .option('-H, --html', 'emit HTML to <sheetname> or <file>.html')
-    .option('-D, --dif', 'emit DIF  to <sheetname> or <file>.dif (Lotus DIF)')
-    .option('-U, --dbf', 'emit DBF  to <sheetname> or <file>.dbf (MSVFP DBF)')
-    .option('-K, --sylk', 'emit SYLK to <sheetname> or <file>.slk (Excel SYLK)')
-    .option('-P, --prn', 'emit PRN  to <sheetname> or <file>.prn (Lotus PRN)')
-    .option('-E, --eth', 'emit ETH  to <sheetname> or <file>.eth (Ethercalc)')
-    .option('-t, --txt', 'emit TXT  to <sheetname> or <file>.txt (UTF-8 TSV)')
-    .option('-r, --rtf', 'emit RTF  to <sheetname> or <file>.txt (Table RTF)')
-    .option('--wk1', 'emit WK1  to <sheetname> or <file>.txt (Lotus WK1)')
-    .option('-z, --dump', 'dump internal representation as JSON')
-    .option('--props', 'dump workbook properties as CSV')
-
-    .option('-F, --field-sep <sep>', 'CSV field separator', ",")
-    .option('-R, --row-sep <sep>', 'CSV row separator', "\n")
-    .option('-n, --sheet-rows <num>', 'Number of rows to process (0=all rows)')
-    .option('--codepage <cp>', 'default to specified codepage when ambiguous')
-    .option('--req <module>', 'require module before processing')
-    .option('--sst', 'generate shared string table for XLS* formats')
-    .option('--compress', 'use compression when writing XLSX/M/B and ODS')
-    .option('--read', 'read but do not generate output')
-    .option('--book', 'for single-sheet formats, emit a file per worksheet')
-    .option('--all', 'parse everything; write as much as possible')
-    .option('--dev', 'development mode')
-    .option('--sparse', 'sparse mode')
-    .option('-q, --quiet', 'quiet mode');
-
-  program.on('--help', function () {
-  });
-
-  /* flag, bookType, default ext */
-  var workbook_formats = [
-    ['xlsx', 'xlsx', 'xlsx'],
-    ['xlsm', 'xlsm', 'xlsm'],
-    ['xlam', 'xlam', 'xlam'],
-    ['xlsb', 'xlsb', 'xlsb'],
-    ['xls', 'xls', 'xls'],
-    ['xla', 'xla', 'xla'],
-    ['biff5', 'biff5', 'xls'],
-    ['numbers', 'numbers', 'numbers'],
-    ['ods', 'ods', 'ods'],
-    ['fods', 'fods', 'fods'],
-    ['wk3', 'wk3', 'wk3']
-  ];
-  var wb_formats_2 = [
-    ['xlml', 'xlml', 'xls']
-  ];
-  program.parse(process.argv);
-
-  var filename = '', sheetname = '';
-  if (program.args[0]) {
-    filename = program.args[0];
-    if (program.args[1]) sheetname = program.args[1];
-  }
-  if (program.sheet) sheetname = program.sheet;
-  if (program.file) filename = program.file;
-
-  if (!filename) {
-    console.error(n + ": must specify a filename");
-    process.exit(1);
-  }
-  if (!fs.existsSync(filename)) {
-    console.error(n + ": " + filename + ": No such file or directory");
-    process.exit(2);
-  }
-
-  if (program.req) program.req.split(",").forEach(function (r) {
-    require((fs.existsSync(r) || fs.existsSync(r + '.js')) ? require('path').resolve(r) : r);
-  });
-
-  var opts = {}, wb/*:?Workbook*/;
-  if (program.listSheets) opts.bookSheets = true;
-  if (program.sheetRows) opts.sheetRows = program.sheetRows;
-  if (program.password) opts.password = program.password;
-  var seen = false;
-  function wb_fmt() {
-    seen = true;
-    opts.cellFormula = true;
-    opts.cellNF = true;
-    opts.xlfn = true;
-    if (program.output) sheetname = program.output;
-  }
-  function isfmt(m/*:string*/)/*:boolean*/ {
-    if (!program.output) return false;
-    var t = m.charAt(0) === "." ? m : "." + m;
-    return program.output.slice(-t.length) === t;
-  }
-  workbook_formats.forEach(function (m) { if (program[m[0]] || isfmt(m[0])) { wb_fmt(); } });
-  wb_formats_2.forEach(function (m) { if (program[m[0]] || isfmt(m[0])) { wb_fmt(); } });
-  if (seen) {
-  } else if (program.formulae) opts.cellFormula = true;
-  else opts.cellFormula = false;
-
-  var wopts = ({ WTF: opts.WTF, bookSST: program.sst }/*:any*/);
-  if (program.compress) wopts.compression = true;
-
-  if (program.all) {
-    opts.cellFormula = true;
-    opts.bookVBA = true;
-    opts.cellNF = true;
-    opts.cellHTML = true;
-    opts.cellStyles = true;
-    opts.sheetStubs = true;
-    opts.cellDates = true;
-    wopts.cellFormula = true;
-    wopts.cellStyles = true;
-    wopts.sheetStubs = true;
-    wopts.bookVBA = true;
-  }
-  if (program.sparse) opts.dense = false; else opts.dense = true;
-  if (program.codepage) opts.codepage = +program.codepage;
-
-  if (program.dev) {
-    opts.WTF = true;
-    wb = X.readFile(filename, opts);
-  } else try {
-    wb = X.readFile(filename, opts);
-  } catch (e) {
-    var msg = (program.quiet) ? "" : n + ": error parsing ";
-    msg += filename + ": " + e;
-    console.error(msg);
-    process.exit(3);
-  }
-  if (program.read) process.exit(0);
-  if (!wb) { console.error(n + ": error parsing " + filename + ": empty workbook"); process.exit(0); }
-  /*:: if(!wb) throw new Error("unreachable"); */
-  if (program.listSheets) {
-    console.log((wb.SheetNames || []).join("\n"));
-    process.exit(0);
-  }
-  if (program.dump) {
-    console.log(JSON.stringify(wb));
-    process.exit(0);
-  }
-  if (program.props) {
-    if (wb) dump_props(wb);
-    process.exit(0);
-  }
-
-  /* full workbook formats */
-  workbook_formats.forEach(function (m) {
-    if (program[m[0]] || isfmt(m[0])) {
-      wopts.bookType = m[1];
-      if (wopts.bookType == "numbers") try {
-        var XLSX_ZAHL = require("xlsx/dist/xlsx.zahl");
-        wopts.numbers = XLSX_ZAHL;
-      } catch(e) {}
-      if (wb) X.writeFile(wb, program.output || sheetname || ((filename || "") + "." + m[2]), wopts);
-      process.exit(0);
-    }
-  });
-
-  wb_formats_2.forEach(function (m) {
-    if (program[m[0]] || isfmt(m[0])) {
-      wopts.bookType = m[1];
-      if (wb) X.writeFile(wb, program.output || sheetname || ((filename || "") + "." + m[2]), wopts);
-      process.exit(0);
-    }
-  });
-
-  var target_sheet = sheetname || '';
-  if (target_sheet === '') {
-    if (+program.sheetIndex < (wb.SheetNames || []).length) target_sheet = wb.SheetNames[+program.sheetIndex];
-    else target_sheet = (wb.SheetNames || [""])[0];
-  }
-
-  var ws;
-  try {
-    ws = wb.Sheets[target_sheet];
-    if (!ws) {
-      console.error("Sheet " + target_sheet + " cannot be found");
-      process.exit(3);
-    }
-  } catch (e) {
-    console.error(n + ": error parsing " + filename + " " + target_sheet + ": " + e);
-    process.exit(4);
-  }
-
-  if (!program.quiet && !program.book) console.error(target_sheet);
-
-  /* single worksheet file formats */
-  [
-    ['biff2', '.xls'],
-    ['biff3', '.xls'],
-    ['biff4', '.xls'],
-    ['sylk', '.slk'],
-    ['html', '.html'],
-    ['prn', '.prn'],
-    ['eth', '.eth'],
-    ['rtf', '.rtf'],
-    ['txt', '.txt'],
-    ['dbf', '.dbf'],
-    ['wk1', '.wk1'],
-    ['dif', '.dif']
-  ].forEach(function (m) {
-    if (program[m[0]] || isfmt(m[1])) {
-      wopts.bookType = m[0];
-      if (program.book) {
-        /*:: if(wb == null) throw new Error("Unreachable"); */
-        wb.SheetNames.forEach(function (n, i) {
-          wopts.sheet = n;
-          X.writeFile(wb, (program.output || sheetname || filename || "") + m[1] + "." + i, wopts);
-        });
-      } else X.writeFile(wb, program.output || sheetname || ((filename || "") + m[1]), wopts);
-      process.exit(0);
-    }
-  });
-
-  function outit(o, fn) { if (fn) fs.writeFileSync(fn, o); else console.log(o); }
-
-  function doit(cb) {
-    /*:: if(!wb) throw new Error("unreachable"); */
-    if (program.book) wb.SheetNames.forEach(function (n, i) {
-      /*:: if(!wb) throw new Error("unreachable"); */
-      outit(cb(wb.Sheets[n]), (program.output || sheetname || filename) + "." + i);
-    });
-    else outit(cb(ws), program.output);
-  }
-
-  var jso = {};
-  switch (true) {
-    case program.formulae:
-      doit(function (ws) { return X.utils.sheet_to_formulae(ws).join("\n"); });
-      break;
-
-    case program.arrays: jso.header = 1;
-    /* falls through */
-    case program.rawJs: jso.raw = true;
-    /* falls through */
-    case program.json:
-      doit(function (ws) { return JSON.stringify(X.utils.sheet_to_json(ws, jso)); });
-      break;
-
-    default:
-      if (!program.book) {
-        var stream = X.stream.to_csv(ws, { FS: program.fieldSep, RS: program.rowSep });
-        if (program.output) stream.pipe(fs.createWriteStream(program.output));
-        else stream.pipe(process.stdout);
-      } else doit(function (ws) { return X.utils.sheet_to_csv(ws, { FS: program.fieldSep, RS: program.rowSep }); });
-      break;
-  }
-
-  function dump_props(wb/*:Workbook*/) {
-    var propaoa = [];
-    if (Object.assign && Object.entries) propaoa = Object.entries(Object.assign({}, wb.Props, wb.Custprops));
-    else {
-      var Keys/*:: :Array<string> = []*/, pi;
-      if (wb.Props) {
-        Keys = Object.keys(wb.Props);
-        for (pi = 0; pi < Keys.length; ++pi) {
-          if (Object.prototype.hasOwnProperty.call(Keys, Keys[pi])) propaoa.push([Keys[pi], Keys[/*::+*/Keys[pi]]]);
-        }
-      }
-      if (wb.Custprops) {
-        Keys = Object.keys(wb.Custprops);
-        for (pi = 0; pi < Keys.length; ++pi) {
-          if (Object.prototype.hasOwnProperty.call(Keys, Keys[pi])) propaoa.push([Keys[pi], Keys[/*::+*/Keys[pi]]]);
-        }
-      }
-    }
-    console.log(X.utils.sheet_to_csv(X.utils.aoa_to_sheet(propaoa)));
-  }
-}
-
-module.exports = run;
+#!/usr/bin/env node
+/* index.js (C) 2020-present  SheetJS -- http://sheetjs.com */
+/* eslint-env node */
+/* vim: set ts=2 ft=javascript: */
+
+var n = "xlsx-cli";
+var X = require('xlsx');
+require('exit-on-epipe');
+var fs = require('fs'), program = require('commander');
+function run() {
+  program
+    .version(X.version)
+    .usage('[options] <file> [sheetname]')
+    .option('-f, --file <file>', 'use specified workbook')
+    .option('-s, --sheet <sheet>', 'print specified sheet (default first sheet)')
+    .option('-N, --sheet-index <idx>', 'use specified sheet index (0-based)')
+    .option('-p, --password <pw>', 'if file is encrypted, try with specified pw')
+    .option('-l, --list-sheets', 'list sheet names and exit')
+    .option('-o, --output <file>', 'output to specified file')
+
+    .option('-B, --xlsb', 'emit XLSB to <sheetname> or <file>.xlsb')
+    .option('-M, --xlsm', 'emit XLSM to <sheetname> or <file>.xlsm')
+    .option('-X, --xlsx', 'emit XLSX to <sheetname> or <file>.xlsx')
+    .option('-I, --xlam', 'emit XLAM to <sheetname> or <file>.xlam')
+    .option('-Y, --ods', 'emit ODS  to <sheetname> or <file>.ods')
+    .option('-8, --xls', 'emit XLS  to <sheetname> or <file>.xls (BIFF8)')
+    .option('-5, --biff5', 'emit XLS  to <sheetname> or <file>.xls (BIFF5)')
+    .option('-4, --biff4', 'emit XLS  to <sheetname> or <file>.xls (BIFF4)')
+    .option('-3, --biff3', 'emit XLS  to <sheetname> or <file>.xls (BIFF3)')
+    .option('-2, --biff2', 'emit XLS  to <sheetname> or <file>.xls (BIFF2)')
+    .option('-i, --xla', 'emit XLA to <sheetname> or <file>.xla')
+    .option('-6, --xlml', 'emit SSML to <sheetname> or <file>.xls (2003 XML)')
+    .option('-T, --fods', 'emit FODS to <sheetname> or <file>.fods (Flat ODS)')
+    .option('--wk3', 'emit WK3  to <sheetname> or <file>.txt (Lotus WK3)')
+    .option('--numbers', 'emit NUMBERS to <sheetname> or <file>.numbers')
+
+    .option('-S, --formulae', 'emit list of values and formulae')
+    .option('-j, --json', 'emit formatted JSON (all fields text)')
+    .option('-J, --raw-js', 'emit raw JS object (raw numbers)')
+    .option('-A, --arrays', 'emit rows as JS objects (raw numbers)')
+    .option('-H, --html', 'emit HTML to <sheetname> or <file>.html')
+    .option('-D, --dif', 'emit DIF  to <sheetname> or <file>.dif (Lotus DIF)')
+    .option('-U, --dbf', 'emit DBF  to <sheetname> or <file>.dbf (MSVFP DBF)')
+    .option('-K, --sylk', 'emit SYLK to <sheetname> or <file>.slk (Excel SYLK)')
+    .option('-P, --prn', 'emit PRN  to <sheetname> or <file>.prn (Lotus PRN)')
+    .option('-E, --eth', 'emit ETH  to <sheetname> or <file>.eth (Ethercalc)')
+    .option('-t, --txt', 'emit TXT  to <sheetname> or <file>.txt (UTF-8 TSV)')
+    .option('-r, --rtf', 'emit RTF  to <sheetname> or <file>.txt (Table RTF)')
+    .option('--wk1', 'emit WK1  to <sheetname> or <file>.txt (Lotus WK1)')
+    .option('-z, --dump', 'dump internal representation as JSON')
+    .option('--props', 'dump workbook properties as CSV')
+
+    .option('-F, --field-sep <sep>', 'CSV field separator', ",")
+    .option('-R, --row-sep <sep>', 'CSV row separator', "\n")
+    .option('-n, --sheet-rows <num>', 'Number of rows to process (0=all rows)')
+    .option('--dateFormat <string>', 'output date format, for example yyyy-mm-dd')
+    .option('--codepage <cp>', 'default to specified codepage when ambiguous')
+    .option('--req <module>', 'require module before processing')
+    .option('--sst', 'generate shared string table for XLS* formats')
+    .option('--compress', 'use compression when writing XLSX/M/B and ODS')
+    .option('--read', 'read but do not generate output')
+    .option('--book', 'for single-sheet formats, emit a file per worksheet')
+    .option('--all', 'parse everything; write as much as possible')
+    .option('--dev', 'development mode')
+    .option('--sparse', 'sparse mode')
+    .option('-q, --quiet', 'quiet mode');
+
+  program.on('--help', function () {
+  });
+
+  /* flag, bookType, default ext */
+  var workbook_formats = [
+    ['xlsx', 'xlsx', 'xlsx'],
+    ['xlsm', 'xlsm', 'xlsm'],
+    ['xlam', 'xlam', 'xlam'],
+    ['xlsb', 'xlsb', 'xlsb'],
+    ['xls', 'xls', 'xls'],
+    ['xla', 'xla', 'xla'],
+    ['biff5', 'biff5', 'xls'],
+    ['numbers', 'numbers', 'numbers'],
+    ['ods', 'ods', 'ods'],
+    ['fods', 'fods', 'fods'],
+    ['wk3', 'wk3', 'wk3']
+  ];
+  var wb_formats_2 = [
+    ['xlml', 'xlml', 'xls']
+  ];
+  program.parse(process.argv);
+
+  var filename = '', sheetname = '';
+  if (program.args[0]) {
+    filename = program.args[0];
+    if (program.args[1]) sheetname = program.args[1];
+  }
+  if (program.sheet) sheetname = program.sheet;
+  if (program.file) filename = program.file;
+
+  if (!filename) {
+    console.error(n + ": must specify a filename");
+    process.exit(1);
+  }
+  if (!fs.existsSync(filename)) {
+    console.error(n + ": " + filename + ": No such file or directory");
+    process.exit(2);
+  }
+
+  if (program.req) program.req.split(",").forEach(function (r) {
+    require((fs.existsSync(r) || fs.existsSync(r + '.js')) ? require('path').resolve(r) : r);
+  });
+
+  var opts = {}, wb/*:?Workbook*/;
+  if (program.listSheets) opts.bookSheets = true;
+  if (program.sheetRows) opts.sheetRows = program.sheetRows;
+  if (program.password) opts.password = program.password;
+  var seen = false;
+  function wb_fmt() {
+    seen = true;
+    opts.cellFormula = true;
+    opts.cellNF = true;
+    opts.xlfn = true;
+    if (program.output) sheetname = program.output;
+  }
+  function isfmt(m/*:string*/)/*:boolean*/ {
+    if (!program.output) return false;
+    var t = m.charAt(0) === "." ? m : "." + m;
+    return program.output.slice(-t.length) === t;
+  }
+  workbook_formats.forEach(function (m) { if (program[m[0]] || isfmt(m[0])) { wb_fmt(); } });
+  wb_formats_2.forEach(function (m) { if (program[m[0]] || isfmt(m[0])) { wb_fmt(); } });
+  if (seen) {
+  } else if (program.formulae) opts.cellFormula = true;
+  else opts.cellFormula = false;
+
+  var wopts = ({ WTF: opts.WTF, bookSST: program.sst }/*:any*/);
+  if (program.compress) wopts.compression = true;
+
+  if (program.all) {
+    opts.cellFormula = true;
+    opts.bookVBA = true;
+    opts.cellNF = true;
+    opts.cellHTML = true;
+    opts.cellStyles = true;
+    opts.sheetStubs = true;
+    opts.cellDates = true;
+    wopts.cellFormula = true;
+    wopts.cellStyles = true;
+    wopts.sheetStubs = true;
+    wopts.bookVBA = true;
+  }
+  if (program.sparse) opts.dense = false; else opts.dense = true;
+  if (program.codepage) opts.codepage = +program.codepage;
+  if(program.dateFormat) opts.dateNF = program.dateFormat;
+
+  if (program.dev) {
+    opts.WTF = true;
+    wb = X.readFile(filename, opts);
+  } else try {
+    wb = X.readFile(filename, opts);
+  } catch (e) {
+    var msg = (program.quiet) ? "" : n + ": error parsing ";
+    msg += filename + ": " + e;
+    console.error(msg);
+    process.exit(3);
+  }
+  if (program.read) process.exit(0);
+  if (!wb) { console.error(n + ": error parsing " + filename + ": empty workbook"); process.exit(0); }
+  /*:: if(!wb) throw new Error("unreachable"); */
+  if (program.listSheets) {
+    console.log((wb.SheetNames || []).join("\n"));
+    process.exit(0);
+  }
+  if (program.dump) {
+    console.log(JSON.stringify(wb));
+    process.exit(0);
+  }
+  if (program.props) {
+    if (wb) dump_props(wb);
+    process.exit(0);
+  }
+
+  /* full workbook formats */
+  workbook_formats.forEach(function (m) {
+    if (program[m[0]] || isfmt(m[0])) {
+      wopts.bookType = m[1];
+      if (wopts.bookType == "numbers") try {
+        var XLSX_ZAHL = require("xlsx/dist/xlsx.zahl");
+        wopts.numbers = XLSX_ZAHL;
+      } catch(e) {}
+      if (wb) X.writeFile(wb, program.output || sheetname || ((filename || "") + "." + m[2]), wopts);
+      process.exit(0);
+    }
+  });
+
+  wb_formats_2.forEach(function (m) {
+    if (program[m[0]] || isfmt(m[0])) {
+      wopts.bookType = m[1];
+      if (wb) X.writeFile(wb, program.output || sheetname || ((filename || "") + "." + m[2]), wopts);
+      process.exit(0);
+    }
+  });
+
+  var target_sheet = sheetname || '';
+  if (target_sheet === '') {
+    if (+program.sheetIndex < (wb.SheetNames || []).length) target_sheet = wb.SheetNames[+program.sheetIndex];
+    else target_sheet = (wb.SheetNames || [""])[0];
+  }
+
+  var ws;
+  try {
+    ws = wb.Sheets[target_sheet];
+    if (!ws) {
+      console.error("Sheet " + target_sheet + " cannot be found");
+      process.exit(3);
+    }
+  } catch (e) {
+    console.error(n + ": error parsing " + filename + " " + target_sheet + ": " + e);
+    process.exit(4);
+  }
+
+  if (!program.quiet && !program.book) console.error(target_sheet);
+
+  /* single worksheet file formats */
+  [
+    ['biff2', '.xls'],
+    ['biff3', '.xls'],
+    ['biff4', '.xls'],
+    ['sylk', '.slk'],
+    ['html', '.html'],
+    ['prn', '.prn'],
+    ['eth', '.eth'],
+    ['rtf', '.rtf'],
+    ['txt', '.txt'],
+    ['dbf', '.dbf'],
+    ['wk1', '.wk1'],
+    ['dif', '.dif']
+  ].forEach(function (m) {
+    if (program[m[0]] || isfmt(m[1])) {
+      wopts.bookType = m[0];
+      if (program.book) {
+        /*:: if(wb == null) throw new Error("Unreachable"); */
+        wb.SheetNames.forEach(function (n, i) {
+          wopts.sheet = n;
+          X.writeFile(wb, (program.output || sheetname || filename || "") + m[1] + "." + i, wopts);
+        });
+      } else X.writeFile(wb, program.output || sheetname || ((filename || "") + m[1]), wopts);
+      process.exit(0);
+    }
+  });
+
+  function outit(o, fn) { if (fn) fs.writeFileSync(fn, o); else console.log(o); }
+
+  function doit(cb) {
+    /*:: if(!wb) throw new Error("unreachable"); */
+    if (program.book) wb.SheetNames.forEach(function (n, i) {
+      /*:: if(!wb) throw new Error("unreachable"); */
+      outit(cb(wb.Sheets[n]), (program.output || sheetname || filename) + "." + i);
+    });
+    else outit(cb(ws), program.output);
+  }
+
+  var jso = {};
+  switch (true) {
+    case program.formulae:
+      doit(function (ws) { return X.utils.sheet_to_formulae(ws).join("\n"); });
+      break;
+
+    case program.arrays: jso.header = 1;
+    /* falls through */
+    case program.rawJs: jso.raw = true;
+    /* falls through */
+    case program.json:
+      doit(function (ws) { return JSON.stringify(X.utils.sheet_to_json(ws, jso)); });
+      break;
+
+    default:
+      if (!program.book) {
+        var stream = X.stream.to_csv(ws, { FS: program.fieldSep, RS: program.rowSep });
+        if (program.output) stream.pipe(fs.createWriteStream(program.output));
+        else stream.pipe(process.stdout);
+      } else doit(function (ws) { return X.utils.sheet_to_csv(ws, { FS: program.fieldSep, RS: program.rowSep }); });
+      break;
+  }
+
+  function dump_props(wb/*:Workbook*/) {
+    var propaoa = [];
+    if (Object.assign && Object.entries) propaoa = Object.entries(Object.assign({}, wb.Props, wb.Custprops));
+    else {
+      var Keys/*:: :Array<string> = []*/, pi;
+      if (wb.Props) {
+        Keys = Object.keys(wb.Props);
+        for (pi = 0; pi < Keys.length; ++pi) {
+          if (Object.prototype.hasOwnProperty.call(Keys, Keys[pi])) propaoa.push([Keys[pi], Keys[/*::+*/Keys[pi]]]);
+        }
+      }
+      if (wb.Custprops) {
+        Keys = Object.keys(wb.Custprops);
+        for (pi = 0; pi < Keys.length; ++pi) {
+          if (Object.prototype.hasOwnProperty.call(Keys, Keys[pi])) propaoa.push([Keys[pi], Keys[/*::+*/Keys[pi]]]);
+        }
+      }
+    }
+    console.log(X.utils.sheet_to_csv(X.utils.aoa_to_sheet(propaoa)));
+  }
+}
+
+module.exports = run;