Un saggio umanistico con bibliografia 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 ≥ 1.25.0
import {
  buildDocumentWithFonts, renderPageToCanvas, 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 = 'en'; // @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',
};
// Every colour is linked to its palette entry by id.
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 = () => ({
  locale: t({ en: 'en-us', es: 'es' }), // hyphenation patterns and the engine's own words
  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: [
      // parity 'any': an essay starts on the next page, left or right.
      { 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`---
Esempio Markdown · 95 righe · content.en.md
title: "Cold Pastoral"
author: "Helena Ward"
---

# Cold Pastoral {#essay kicker="Essays · Romantic Poetry" sub="On the voice in the last two lines of Keats’s “Ode on a Grecian Urn”" byline="Helena Ward"}

No Greek urn answers to the one Keats describes. Readers who went looking for it in the British Museum found parts of several: the heifer led to sacrifice on the Parthenon frieze, which Keats saw among the Elgin Marbles in the spring of 1817, and the Bacchic dancers of the Townley Vase, with those of the Borghese Vase in the Louvre, known in London through engravings [@jack1967]. The nearest thing to a single source is a sheet of paper. Keats traced an engraving of the Sosibios Vase, a marble krater signed by an Athenian sculptor of the first century BCE, from Henry Moses’s book of antique vases, and the tracing survives [@mcdermott1948]. The urn of the poem is a composite, assembled from marbles and from prints of marbles, and at the end it speaks.

Keats wrote the ode in May 1819. It was first printed in January 1820 in the *Annals of the Fine Arts*, a London magazine about painting and sculpture, and that summer he collected it in his third and last book of poems. The two printings differ in one mark of punctuation, and much of what has been written about the poem since turns on that mark.

## The questions

The ode opens by naming its object three times, as a “still unravish’d bride of quietness,” a “foster-child of silence and slow time” and a “Sylvan historian” [@keats-ode, lines 1–3]. The names are a courtesy: the speaker wants the historian to tell its tale. “What men or gods are these? What maidens loth? / What mad pursuit? What struggle to escape?” (8–9). The urn does not answer, and for three stanzas the speaker answers for it, praising the “unheard” melodies of the painted pipes over heard ones (11–12) and a lover who will never reach the girl but will always love her.

The fourth stanza turns from the dancers to a procession, a priest leading a heifer “lowing at the skies” (33), and then to a town that is not on the urn at all, emptied of its people by the sacrifice and left silent “for evermore” (38). Here the questions stop being answerable even in principle. The town exists only because the procession has to have come from somewhere.

## The punctuation of the last lines

In the last stanza the speaker gives up questioning. The urn “dost tease us out of thought / As doth eternity: Cold Pastoral!” (44–45), and it will outlast this generation as “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). In the 1820 volume the inverted commas close after “beauty,” so the urn says five words and someone else says the rest. The *Annals* text has no inverted commas, and @stillinger1974 records that neither have the transcripts made by Keats’s friends. An editor has to choose, and the choice decides who says “that is all”: the urn to mankind, the poet to his reader, or the poet to the figures on the urn.

The lines have had hostile readers. T. S. Eliot found the couplet “a serious blemish on a beautiful poem” [-@eliot1932, 230], a statement that was either untrue or one he could not understand. Cleanth Brooks answered that the words are “a speech ‘in character’” [-@brooks1947, 165], fitted to the urn that utters them, and set them beside Edgar’s “Ripeness is all” in *King Lear*. His reading needs the 1820 punctuation: if the urn speaks only the five words inside the commas, the motto is the urn’s, and the comment after the dash belongs to the poet who has listened to it.

## The letters

Keats had written about beauty and truth before he wrote about the urn. “What the Imagination seizes as Beauty must be truth—whether it existed before or not,” he told Benjamin Bailey in November 1817 [@keats-letters, 41]. A month later, walking home from the Christmas pantomime, he named the quality he thought a poet most needed:

:::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}

Read with the letter beside it, the couplet is less a doctrine than a refusal. The urn has answered none of the speaker’s questions about who the figures are or where the town stands. What it offers instead is a sentence that cannot be checked, and the poet’s comment accepts that this is all the urn will give. The speaker who began by demanding a tale ends content with half knowledge, which is the state the letter asks a poet to bear.

## Works Cited {style="works-cited"}

:::bibliography{title=""}

:::paragraphs{style="colophon"}
Set in Spectral and Spectral SC (SIL OFL). Text: original essay, CC BY 4.0; quotations from Keats’s 1820 volume and Colvin’s edition of the letters.
:::

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

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

// ─── 4 · Build & show ───────────────────────────────────────────────────────
const doc = await buildDocumentWithFonts({ markdown }, config(), kitFonts(FONTS));
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: uguale in ogni ricetta · 269 righe
// ─── 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 v3 ── the same in every recipe · postext.dev/cookbook
// Postext loads the faces a config asks for before layout (prepareFonts,
// buildDocumentWithFonts) and asks the kit for the files: Fontsource's, the
// files the PDF embeds too.

/** The options of buildDocumentWithFonts / prepareFonts / withLoadedFonts:
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function kitFonts(FONTS = {}) {
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}

/** The unicode-range of each Fontsource file the kit loads (a function: the
 *  kit is inlined after the pen's code, which runs before a const would be set). */
function kitRanges() {
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}

/** A loaded FontFace covers this family, weight and style (fonts.check() would
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function hasFace(family, weight, style) {
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}

/** The files beyond latin `text` needs that `meta`'s family ships. */
function kitSubsetsFor(text, meta) {
  return [[/[Ā-˿ᴀ-ᶿḀ-ỿ†ℓⱠ-Ɀ꜠-ꟿ]/u, 'latin-ext'], [/[Ͱ-Ͽ]/u, 'greek']]
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}

/** Fontsource's id for a family: 'Source Serif 4' → 'source-serif-4'. */
function fontsourceId(family) { return family.toLowerCase().replace(/\s+/g, '-'); }

/** A package's folder at the one version @5 names now (#766). */
function fontsourceAt(id, u = `https://cdn.jsdelivr.net/npm/@fontsource/${id}@`) {
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/** The family's Fontsource metadata (weights, styles, subsets), or null. */
function fontsourceMeta(family) {
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      .then((res) => (res.ok ? res.json() : null), () => null));
  }
  return fontsourceMeta.cache.get(id);
}

// ─── Kit · viewer v2 ── the same in every recipe · postext.dev/cookbook
/** The pages as spreads on a dark desk, page 1 alone, then verso | recto,
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function showPages(docs, { title, width = 460, ...render } = {}) {
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      .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 v3 ── the same in every recipe that exports a PDF
/** The Fontsource files the screen used, as TrueType, with their range and
 *  place: the nearest weight the family ships, upright with no italic;
 *  latin, then what its letters need (kitSubsetsFor). */
async function fontsourceProvider(family, weight, style, request) {
  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 text = String.fromCodePoint(...(request?.codePoints ?? []));
  const files = await Promise.all(['latin', ...kitSubsetsFor(text, meta)].map(async (subset, order) => {
    const res = await fetch(`${await fontsourceAt(id)}files/${id}-${subset}-${w}-${s}.woff2`);
    if (!res.ok) throw new Error(`Fontsource has no ${family} ${w} ${s} ${subset}`);
    return Object.assign(await decompressWoff2(new Uint8Array(await res.arrayBuffer())),
      { unicodeRange: kitRanges()[subset], order });
  }));
  return files.length === 1 ? files[0] : files;
}

/** A "Build the PDF" button; then "Open the PDF" (a new tab: CodePen's frame
 *  shows no 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 ───────────────────────────────────────────────────────────────────────