Un assaig d'humanitats amb obres citades en MLA

// ═══ Postext Cookbook · Nº 096 · A humanities essay with MLA works cited ══════════
// https://postext.dev/en/cookbook/mla-humanities-essay
// Code: MIT · Text: original (CC BY 4.0) · Pictures: none
// Fonts: Spectral, Spectral SC (SIL OFL 1.1) · Needs postext ≥ 1.12.1
import {
  buildDocument, renderPageToCanvas, clearMeasurementCache, registerCitationEngine,
} from 'https://esm.sh/postext';
import { renderToPdf, decompressWoff2 } from 'https://esm.sh/postext-pdf';
import { createCiteprocEngine, STYLES, LOCALES } from 'https://esm.sh/postext-citeproc';

const LANG = 'es'; // @lang: the language of the sample document ('en' | 'es')
const RECIPE = 'mla-humanities-essay';

// ─── 1 · Design ─────────────────────────────────────────────────────────────
// #region palette: the black glaze and the red clay of an Attic vase
const palette = {
  ink: '#1f1a17', glaze: '#231c19', clay: '#9a3d22', slip: '#e3a27e', rule: '#c9bdb0',
  muted: '#6b6159', paper: '#fffdf9',
};
// A design element paints the hex written beside its paletteId (gotcha: palette-skips-designs).
const col = (id) => ({ hex: palette[id], model: 'hex', paletteId: id });
const colorPalette = Object.entries({ ...palette, 'main-color': palette.clay })
  .map(([id, hex]) => ({ id, name: id, value: { hex, model: 'hex' } }));
// #endregion
const TEXT = 'Spectral', LABEL = 'Spectral SC';
const TRIM = { width: 150, height: 230 }; // a literary quarterly
const MARGIN = { top: 22, bottom: 22, inner: 19, outer: 21 };
const LEAD = 14.4; // pt
const at = (to, edge, x = 0, y = 0) => ({ anchor: { to, edge }, offset: { x: mm(x), y: mm(y) } });

// #region answer: MLA 9 author-page citations and a Works Cited list
// The text cites with [@keats-letters, 48] → (Keats, Letters 48): MLA prints the author
// and the page, and adds a short title when two works share an author. [-@eliot1932, 230]
// drops the name the sentence already gives → (230). The list is alphabetical, and a
// second work by the same author opens with a dash (MLA's ---) instead of the name.
registerCitationEngine(createCiteprocEngine({ styles: STYLES, locales: LOCALES }));
const citations = {
  style: 'modern-language-association', // MLA 9th edition, author-page
  link: true, // a citation jumps to its entry in Works Cited
  bibliography: {
    // MLA's half-inch hanging indent, scaled to a 108 mm measure.
    fontSize: em(0.94), lineHeight: pt(13.4), hangingIndent: em(2.2), entrySpacing: pt(3),
  },
};
// #endregion

// #region quotation: a block quotation, set in and upright
// More than four lines of prose go in a Markdown blockquote: in ink, indented, with no
// first-line indent. Its citation follows the final full stop, as MLA asks.
const blockquote = {
  color: col('ink'), italic: false, indent: em(2), firstLineIndent: em(0),
};
// #endregion

// #region opener: the title in a band of black glaze with a red clay foot
const BAND = 116; // mm from the trim's top
const opener = {
  enabled: true,
  minHeight: mm(BAND - MARGIN.top + 4), // the text starts a line under the band
  slot: { elements: [
    { kind: 'box', id: 'band', style: { backgroundColor: col('glaze') },
      placement: { ...at('page', 'top-left'), size: { width: 'fill', height: mm(BAND) } } },
    { kind: 'box', id: 'foot', style: { backgroundColor: col('clay') },
      placement: { ...at('page', 'top-left', 0, BAND - 3), size: { width: 'fill',
        height: mm(3) } } },
    { kind: 'text', id: 'kicker', content: '{attr.kicker}', fontFamily: LABEL, fontWeight: 600,
      fontSize: pt(9), letterSpacing: pt(1.6), color: col('slip'), align: 'left',
      placement: at('container', 'top-left', 0, 6) },
    { kind: 'text', id: 'title', content: '{titleText}', fontFamily: TEXT, fontWeight: 300,
      italic: true, fontSize: pt(56), lineHeight: 0.95, color: col('paper'), align: 'left',
      overflow: 'wrap', placement: { ...at('container', 'top-left', -1, 30),
        size: { width: mm(110), height: 'auto' } } },
    { kind: 'text', id: 'sub', content: '{attr.sub}', fontFamily: TEXT, fontWeight: 300,
      fontSize: pt(13), lineHeight: 1.25, color: col('paper'), align: 'left', overflow: 'wrap',
      placement: { ...at('container', 'top-left', 0, 66),
        size: { width: mm(96), height: 'auto' } } },
    { kind: 'text', id: 'byline', content: '{attr.byline}', fontFamily: LABEL, fontWeight: 600,
      fontSize: pt(9.5), letterSpacing: pt(1.2), color: col('slip'), align: 'left',
      placement: at('container', 'top-left', 0, 82) },
  ] },
};
// #endregion

const head = (id, content, parity, edge, x, align) => ({
  kind: 'text', id, content, parity, pages: 'body', fontFamily: LABEL, fontWeight: 500,
  fontSize: pt(8.5), letterSpacing: pt(1), color: col('muted'), align,
  placement: at('page', edge, x, 12),
});

const config = () => ({ // a factory: the engine caches resolved configs per object
  locale: t({ en: 'en-us', es: 'es' }), // exact codes (gotcha: hyphenation-locales)
  colorPalette,
  citations,
  page: {
    sizePreset: 'custom', width: mm(TRIM.width), height: mm(TRIM.height), dpi: 150,
    backgroundColor: col('paper'),
    margins: { top: mm(MARGIN.top), bottom: mm(MARGIN.bottom), left: mm(MARGIN.inner),
      right: mm(MARGIN.outer), mirror: true },
  },
  layout: { layoutType: 'single' },
  bodyText: {
    fontFamily: TEXT, fontSize: pt(10.6), lineHeight: pt(LEAD), color: col('ink'),
    boldColor: col('ink'), italicColor: col('ink'), referenceColor: col('ink'),
    textAlign: 'justify', firstLineIndent: mm(5), indentAfterHeading: false,
    hyphenation: { enabled: true }, optimalLineBreaking: true,
    avoidWidows: true, avoidOrphans: true, avoidRunts: true, blockquote,
  },
  headings: {
    fontFamily: LABEL, fontWeight: 600, color: col('clay'),
    levels: [
      // Restated: any headings object drops the H1 break (gotcha: headings-drop-h1-break).
      { level: 1, fontFamily: TEXT, fontSize: pt(56), marginBottom: pt(0),
        breakBefore: { enabled: true, parity: 'any' }, advancedDesign: opener },
      { level: 2, fontSize: pt(11.5), letterSpacing: pt(0.9), lineHeight: pt(LEAD),
        marginTop: pt(LEAD), marginBottom: pt(LEAD / 2) },
    ],
  },
  // #region works-cited: MLA starts the list on a page of its own
  headingStyles: [{ id: 'works-cited', breakBefore: { enabled: true, parity: 'any' } }],
  // #endregion
  paragraphStyles: [
    { id: 'colophon', fontFamily: LABEL, fontSize: pt(7.5), lineHeight: pt(10),
      color: col('muted'), textAlign: 'left', firstLineIndent: pt(0), marginTop: pt(LEAD * 2) },
  ],
  header: { elements: [
    head('verso-folio', '{pageNumber}', 'even', 'top-left', MARGIN.outer, 'left'),
    head('verso-author', '{attr.byline}', 'even', 'top-left', MARGIN.outer + 8, 'left'),
    head('recto-title', '{title}', 'odd', 'top-right', -(MARGIN.outer + 8), 'right'),
    head('recto-folio', '{pageNumber}', 'odd', 'top-right', -MARGIN.outer, 'right'),
  ] },
  footer: { elements: [ // a drop folio where the running heads stand down
    { ...head('drop-folio', '{pageNumber}', 'all', 'top', 0, 'center'),
      pages: 'opener', placement: at('container', 'top', 0, 9) },
  ] },
});

// ─── 2 · Content ────────────────────────────────────────────────────────────
const markdown = String.raw`---
Mostra en Markdown · 95 línies · content.es.md
title: "Fría pastoral"
author: "Helena Ward"
---

# Fría pastoral {#essay kicker="Ensayos · Poesía romántica" sub="Sobre la voz de los dos últimos versos de la «Ode on a Grecian Urn» de Keats" byline="Helena Ward"}

Ninguna urna griega se corresponde con la que describe Keats. Quienes fueron a buscarla al British Museum encontraron trozos de varias: la novilla que llevan al sacrificio en el friso del Partenón, que Keats vio entre los mármoles de Elgin en la primavera de 1817, y los danzantes báquicos del vaso Townley, junto con los del vaso Borghese del Louvre, que en Londres se conocía por grabados [@jack1967]. Lo más parecido a una fuente única es una hoja de papel. Keats calcó un grabado del vaso Sosibios, una crátera de mármol firmada por un escultor ateniense del siglo I a. C., a partir del libro de vasos antiguos de Henry Moses, y el calco se conserva [@mcdermott1948]. La urna del poema es una suma hecha con mármoles y con estampas de mármoles, y al final habla.

Keats escribió la oda en mayo de 1819. Se imprimió por primera vez en enero de 1820 en los *Annals of the Fine Arts*, una revista londinense de pintura y escultura, y ese verano el poeta la recogió en su tercer y último libro de poemas. Las dos versiones difieren en un signo de puntuación, y buena parte de lo que se ha escrito después sobre el poema gira en torno a ese signo.

## Las preguntas

La oda empieza nombrando tres veces a su objeto: «still unravish’d bride of quietness», «foster-child of silence and slow time» y «Sylvan historian» [@keats-ode, lines 1–3]. Los nombres son una cortesía, porque el hablante quiere que la historiadora le cuente su historia. «What men or gods are these? What maidens loth? / What mad pursuit? What struggle to escape?» (8–9). La urna no contesta, y durante tres estrofas el hablante contesta por ella: prefiere las melodías «unheard» de las flautas pintadas a las que se oyen (11–12) y celebra a un amante que nunca alcanzará a la muchacha pero siempre la amará.

La cuarta estrofa pasa de los danzantes a una procesión, un sacerdote que conduce una novilla «lowing at the skies» (33), y después a un pueblo que ni siquiera está en la urna, vaciado de su gente por el sacrificio y condenado al silencio «for evermore» (38). Aquí las preguntas dejan de tener respuesta posible. El pueblo existe solo porque la procesión tiene que haber salido de algún sitio.

## La puntuación de los últimos versos

En la última estrofa el hablante deja de preguntar. La urna «dost tease us out of thought / As doth eternity: Cold Pastoral!» (44–45) y sobrevivirá a esta generación como «a friend to man, to whom thou say’st, / “Beauty is truth, truth beauty,”—that is all / Ye know on earth, and all ye need to know» (48–50). En el libro de 1820 las comillas se cierran después de «beauty», de modo que la urna dice cinco palabras y el resto lo dice otro. El texto de los *Annals* no lleva comillas, y tampoco las llevan las copias que hicieron los amigos de Keats [@stillinger1974]. Un editor tiene que elegir, y la elección decide quién dice «that is all»: la urna a la humanidad, el poeta a su lector o el poeta a las figuras de la urna.

Los versos han tenido lectores hostiles. T. S. Eliot vio en ellos «a serious blemish on a beautiful poem» [-@eliot1932, 230], una afirmación falsa o que él no alcanzaba a entender. Cleanth Brooks le respondió que las palabras son «a speech ‘in character’» [-@brooks1947, 165], ajustadas a la urna que las pronuncia, y las comparó con el «Ripeness is all» de Edgar en *King Lear*. Su lectura necesita la puntuación de 1820: si la urna dice solo las cinco palabras entre comillas, el lema es de la urna, y el comentario que sigue a la raya pertenece al poeta que la ha escuchado.

## Las cartas

Keats había escrito sobre la belleza y la verdad antes de escribir sobre la urna. «What the Imagination seizes as Beauty must be truth—whether it existed before or not», le dijo a Benjamin Bailey en noviembre de 1817 [@keats-letters, 41]. Un mes después, de vuelta de la pantomima de Navidad, dio nombre a la cualidad que a su juicio más necesitaba un poeta:

:::space{lines=0.5}

> I had not a dispute, but a disquisition, with Dilke upon various subjects; several things dove-tailed in my mind, and at once it struck me what quality went to form a Man of Achievement, especially in Literature, and which Shakspeare possessed so enormously—I mean Negative Capability, that is, when a man is capable of being in uncertainties, mysteries, doubts, without any irritable reaching after fact and reason. [@keats-letters, 48]

:::space{lines=0.5}

Leído junto a la carta, el dístico final es menos una doctrina que una renuncia. La urna no ha respondido a ninguna de las preguntas del hablante sobre quiénes son las figuras o dónde está el pueblo. Lo que ofrece a cambio es una frase que no se puede comprobar, y el comentario del poeta acepta que eso es todo lo que la urna va a dar. El hablante que empezó exigiendo una historia termina conforme con saber a medias, que es el estado que la carta pide al poeta que soporte.

## Obras citadas {style="works-cited"}

:::bibliography{title=""}

:::paragraphs{style="colophon"}
Compuesto en Spectral y Spectral SC (SIL OFL). Texto: ensayo original, CC BY 4.0; citas del libro de Keats de 1820 y de la edición de sus cartas de Colvin.
:::

:::references{format=csl-yaml}
- id: keats-ode
  type: chapter
  author: [{family: Keats, given: John}]
  title: Ode on a Grecian Urn
  title-short: Ode
  container-title: "Lamia, Isabella, The Eve of St. Agnes, and Other Poems"
  publisher: Taylor and Hessey
  issued: 1820
  page: 113-116
- id: keats-letters
  type: book
  author: [{family: Keats, given: John}]
  editor: [{family: Colvin, given: Sidney}]
  title: Letters of John Keats to His Family and Friends
  title-short: Letters
  publisher: Macmillan
  issued: 1925
- id: jack1967
  type: book
  author: [{family: Jack, given: Ian}]
  title: Keats and the Mirror of Art
  publisher: Clarendon Press
  issued: 1967
- id: mcdermott1948
  type: article-journal
  author: [{family: McDermott, given: William C.}]
  title: Keats and Sosibios
  container-title: The Classical Journal
  volume: 44
  issue: 1
  page: 33-34
  issued: 1948
- id: stillinger1974
  type: book
  author: [{family: Stillinger, given: Jack}]
  title: "The Texts of Keats’s Poems"
  publisher: Harvard UP
  issued: 1974
- id: eliot1932
  type: chapter
  author: [{family: Eliot, given: T. S.}]
  title: Dante
  container-title: "Selected Essays, 1917–1932"
  publisher: Faber and Faber
  issued: 1932
- id: brooks1947
  type: book
  author: [{family: Brooks, given: Cleanth}]
  title: "The Well Wrought Urn: Studies in the Structure of Poetry"
  publisher: Reynal and Hitchcock
  issued: 1947
:::
`;

// ─── 3 · Fonts ──────────────────────────────────────────────────────────────
// Every face the design uses (gotcha: fonts-first).
const FONTS = {
  Spectral: ['300', '300i', '400', '400i', '600', '600i'],
  'Spectral SC': ['400', '500', '600'],
};

// ─── 4 · Build & show ───────────────────────────────────────────────────────
await loadFonts(FONTS, markdown);
const doc = await buildWithFonts(() => buildDocument({ markdown }, config()), markdown);
const title = t({ en: 'A humanities essay with MLA works cited',
  es: 'Un ensayo de humanidades con obras citadas en MLA' });
showPages(doc, { title });
offerPdf(() => renderToPdf(doc, { fontProvider: fontsourceProvider }), `${RECIPE}.pdf`);

Kit · core, fonts, viewer, pdf: igual a totes les receptes · 275 línies
// ─── Kit ── helpers shared by every Cookbook recipe · postext.dev/cookbook ─────

// ─── Kit · core v1 ── the same in every recipe · postext.dev/cookbook ─────────
function mm(value) { return { value, unit: 'mm' }; }
function pt(value) { return { value, unit: 'pt' }; }
function em(value) { return { value, unit: 'em' }; }
/** The sample language's string: t({ en: 'Figure', es: 'Figura' }). */
function t(strings) { return strings[LANG] ?? Object.values(strings)[0]; }
/** A file in this recipe's assets folder, served from the Postext repo by jsDelivr. */
function asset(file) { return `https://cdn.jsdelivr.net/gh/drnachio/postext@main/cookbook/${RECIPE}/assets/${file}`; }

// ─── Kit · fonts v1 ── the same in every recipe · postext.dev/cookbook ────────
// Postext measures text with the faces the browser has loaded, and caches the
// widths, so every face must be ready before the first build. Faces come from
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// ─── Kit · viewer v1 ── the same in every recipe · postext.dev/cookbook ───────
/** Shows the pages as facing spreads on a dark desk: the first page is a
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        canvas.postext = p;
        canvas.style.aspectRatio = `${p.page.width} / ${p.page.height}`;
        canvas.setAttribute('role', 'img');
        canvas.setAttribute('aria-label', `Page ${label}`);
        const folio = document.createElement('figcaption');
        folio.textContent = label;
        figure.append(canvas, folio);
        painter.observe(canvas);
      } else figure.className = 'pt-blank';
      spread.append(figure);
    }
    return spread;
  }));
  kitStatus(`${pages.length} ${pages.length === 1 ? 'page' : 'pages'}`);
  document.documentElement.dataset.postext = 'ready';
  return pages.length;
}

/** The desk, the bar and the error reporting, created once. */
function viewer(title) {
  if (!document.getElementById('pt-kit')) {
    document.head.insertAdjacentHTML('beforeend', `<style id="pt-kit">
      :root { color-scheme: dark; }
      body { margin: 0; background: #0e1014; color: #b9bcc4; font: 13px/1.45 system-ui, sans-serif; }
      #pt-bar { position: sticky; top: 0; z-index: 1; display: flex; flex-wrap: wrap; align-items: center;
        gap: 6px 16px; padding: 10px 16px; background: rgb(14 16 20 / .92); backdrop-filter: blur(6px);
        border-bottom: 1px solid #23262d; }
      #pt-bar strong { color: #f4f1ea; font-weight: 600; }
      #pt-actions { display: flex; gap: 12px; margin-left: auto; }
      #pt-actions a, #pt-actions button { color: #d8a21a; font: inherit; background: none; border: 0; padding: 0; cursor: pointer; }
      #pages { display: grid; justify-items: center; gap: 48px; padding: 32px 16px 72px; }
      .pt-spread { display: flex; }
      .pt-spread figure { margin: 0; width: min(460px, 44vw); }
      .pt-spread canvas { display: block; width: 100%; background: #fff;
        box-shadow: 0 1px 2px rgb(0 0 0 / .5), 0 22px 44px -16px rgb(0 0 0 / .8); }
      .pt-spread figure:first-child canvas { box-shadow: inset -14px 0 14px -14px rgb(0 0 0 / .18), 0 1px 2px rgb(0 0 0 / .5), 0 22px 44px -16px rgb(0 0 0 / .8); }
      .pt-spread figcaption { margin-top: 10px; text-align: center; font: 600 10px/1 system-ui, sans-serif;
        letter-spacing: .18em; text-transform: uppercase; color: #6c7079; }
      .pt-blank { visibility: hidden; }
      @media (max-width: 760px) {
        .pt-spread { flex-direction: column; gap: 32px; }
        .pt-spread figure { width: min(460px, 92vw); }
        .pt-blank { display: none; }
      }
    </style>`);
    document.body.insertAdjacentHTML('afterbegin',
      '<header id="pt-bar"><strong id="pt-title"></strong><span id="pt-status" role="status"></span><span id="pt-actions"></span></header>');
    document.getElementById('pt-title').textContent = document.title || 'Postext';
    addEventListener('error', (event) => kitFail(event.error ?? event.message));
    addEventListener('unhandledrejection', (event) => kitFail(event.reason));
  }
  if (title) document.getElementById('pt-title').textContent = title;
  return document.getElementById('pages')
    ?? document.body.appendChild(Object.assign(document.createElement('main'), { id: 'pages' }));
}

function kitStatus(text) {
  viewer();
  document.getElementById('pt-status').textContent = text;
}

function kitFail(error) {
  document.documentElement.dataset.postext = 'error';
  kitStatus(`Error: ${error?.message ?? error}`);
}

// ─── Kit · pdf v1 ── the same in every recipe that exports a PDF ──────────────
/** postext-pdf embeds TrueType bytes. Fetch the Fontsource file the screen
 *  used, snapping to a weight the family ships and falling back to upright
 *  when it has no italic: the PDF asks for every face a block could use. */
async function fontsourceProvider(family, weight, style) {
  const id = fontsourceId(family);
  const meta = await fontsourceMeta(family);
  const weights = meta?.weights?.length ? meta.weights : [400, 700];
  const w = weights.reduce((a, b) => (Math.abs(b - weight) < Math.abs(a - weight) ? b : a));
  const s = style === 'italic' && meta && !meta.styles.includes('italic') ? 'normal' : style;
  const res = await fetch(`https://cdn.jsdelivr.net/npm/@fontsource/${id}@5/files/${id}-latin-${w}-${s}.woff2`);
  if (!res.ok) throw new Error(`Fontsource has no ${family} ${w} ${s} (${res.status})`);
  return decompressWoff2(new Uint8Array(await res.arrayBuffer()));
}

/** A "Build the PDF" button in the bar. Once built: "Open the PDF" (a new
 *  tab, since CodePen's preview frame cannot show PDFs) and a download link. */
function offerPdf(makePdf, filename) {
  viewer();
  const button = Object.assign(document.createElement('button'), { type: 'button', textContent: 'Build the PDF' });
  button.dataset.postextPdf = filename;
  button.addEventListener('click', async () => {
    button.disabled = true;
    button.textContent = 'Building the PDF…';
    try {
      const bytes = await makePdf();
      const url = URL.createObjectURL(new Blob([bytes], { type: 'application/pdf' }));
      const size = `${Math.max(1, Math.round(bytes.length / 1024))} KB`;
      button.replaceWith(
        Object.assign(document.createElement('a'), { href: url, target: '_blank', rel: 'noopener', textContent: 'Open the PDF ↗' }),
        Object.assign(document.createElement('a'), { href: url, download: filename, textContent: `Download ${filename} · ${size}` }));
    } catch (error) {
      button.disabled = false;
      button.textContent = 'Build the PDF';
      kitFail(error);
    }
  });
  document.getElementById('pt-actions').append(button);
}

// ─── /Kit ───────────────────────────────────────────────────────────────────────