@thi.ng/markdown-table/table.js

Markdown table formatter/generator with support for column alignments

import { isString } from "@thi.ng/checks/is-string";
import { juxt } from "@thi.ng/compose/juxt";
import { assert } from "@thi.ng/errors/assert";
import { center } from "@thi.ng/strings/center";
import { padLeft } from "@thi.ng/strings/pad-left";
import { padRight } from "@thi.ng/strings/pad-right";
import { repeat } from "@thi.ng/strings/repeat";
import { wrap } from "@thi.ng/strings/wrap";
import { comp } from "@thi.ng/transducers/comp";
import { last } from "@thi.ng/transducers/last";
import { map } from "@thi.ng/transducers/map";
import { max } from "@thi.ng/transducers/max";
import { multiplex } from "@thi.ng/transducers/multiplex";
import { range } from "@thi.ng/transducers/range";
import { repeat as $repeat } from "@thi.ng/transducers/repeat";
import { repeatedly } from "@thi.ng/transducers/repeatedly";
import { scan } from "@thi.ng/transducers/scan";
import { transduce } from "@thi.ng/transducers/transduce";
const PADS = {
  c: center,
  l: padRight,
  r: padLeft
};
const SEPS = {
  c: (x) => `:${repeat("-", x)}:`,
  l: (x) => `:${repeat("-", x + 1)}`,
  r: (x) => `${repeat("-", x + 1)}:`
};
const table = (header, rows, opts = {}) => {
  const numColumns = header.length;
  const align = opts.align || [...$repeat("l", numColumns)];
  assert(align.length === numColumns, `invalid/missing column alignments`);
  opts.bold && (header = header.map(wrap("**")));
  const body = [header, ...rows];
  const widths = transduce(
    multiplex(
      ...[
        ...repeatedly(
          (i) => comp(
            map(
              (row) => row[i] != null ? String(row[i]).length : 0
            ),
            scan(max())
          ),
          numColumns
        )
      ]
    ),
    last(),
    body
  );
  const pads = widths.map((w, i) => PADS[align[i]](w));
  const colIDs = [...range(numColumns)];
  const result = body.map(
    (row) => colIDs.map((i) => `| ${pads[i](__str(row[i]))} `).join("") + "|"
  );
  result.splice(
    1,
    0,
    widths.map((w, i) => `|${SEPS[align[i]](w)}`).join("") + "|"
  );
  return result.join("\n");
};
const tableKeys = (headers, keys, items, opts) => table(
  headers,
  map(
    juxt(
      ...keys.map((k) => isString(k) ? (x) => __str(x[k]) : k)
    ),
    items
  ),
  opts
);
const __str = (x) => x != null ? String(x) : "";
export {
  table,
  tableKeys
};