gistfile1.js

[].map.call(document.querySelectorAll('.toc a'), function(node) { return node.href.split('#')[0] }).reduce(function(output, item) {
    item = item.split("/");
    item = item[item.length - 1];
    if (output.indexOf(item) < 0) output.push(item);
    return output;
}, [""])

multi-page specs

{
    "html5": [
        "Overview.html",
        "introduction.html",
        "infrastructure.html",
        "dom.html",
        "semantics.html",
        "document-metadata.html",
        "sections.html",
        "grouping-content.html",
        "text-level-semantics.html",
        "edits.html",
        "embedded-content-0.html",
        "links.html",
        "tabular-data.html",
        "forms.html",
        "interactive-elements.html",
        "scripting-1.html",
        "common-idioms.html",
        "disabled-elements.html",
        "browsers.html",
        "webappapis.html",
        "editing.html",
        "syntax.html",
        "the-xhtml-syntax.html",
        "rendering.html",
        "obsolete.html",
        "iana.html",
        "index.html",
        "references.html",
        "acknowledgments.html"
    ],
    "CSS21": [
        "about.html",
        "intro.html",
        "conform.html",
        "syndata.html",
        "selector.html",
        "cascade.html",
        "media.html",
        "box.html",
        "visuren.html",
        "visudet.html",
        "visufx.html",
        "generate.html",
        "page.html",
        "colors.html",
        "fonts.html",
        "text.html",
        "tables.html",
        "ui.html",
        "aural.html",
        "refs.html",
        "changes.html",
        "sample.html",
        "zindex.html",
        "propidx.html",
        "grammar.html",
        "leftblank.html"
    ],
    "SVG11": [
        "intro.html",
        "concepts.html",
        "render.html",
        "types.html",
        "struct.html",
        "styling.html",
        "coords.html",
        "paths.html",
        "shapes.html",
        "text.html",
        "painting.html",
        "color.html",
        "pservers.html",
        "masking.html",
        "filters.html",
        "interact.html",
        "linking.html",
        "script.html",
        "animate.html",
        "fonts.html",
        "metadata.html",
        "backward.html",
        "extend.html",
        "svgdtd.html",
        "svgdom.html",
        "idl.html",
        "java.html",
        "escript.html",
        "implnote.html",
        "conform.html",
        "access.html",
        "i18n.html",
        "minimize.html",
        "refs.html",
        "eltindex.html",
        "attindex.html",
        "propidx.html",
        "feature.html",
        "mimereg.html",
        "changes.html"
    ]
}