为什么MathJax.startup.promise未定义

Question

我正在尝试让MathJaX v3在节点上运行，这是我的代码：

const fs = require('fs');
const glob = require('glob');
const { AllPackages } = require('mathjax-full/js/input/tex/AllPackages.js');
glob('**/*.html', { "ignore": ['node_modules/**/*.html'] }, (_, res) =>
res.forEach(r => {
const htmlfile = fs.readFileSync(r, 'utf8');
MathJax = {
loader: {
paths: { mathjax: 'mathjax-full/js', custom: '.' },
require: require,
load: ['[custom]/xypic.min.js'],
},
tex: {
packages: AllPackages.concat('xypic'),
inlineMath: [['$', '$']]
},
startup: {
input: 'tex',
output: 'chtml',
adaptor: 'liteAdaptor',
document: htmlfile,
}
}
require('mathjax-full/js/components/startup.js');
MathJax.startup.promise.then(() => {
const adaptor = MathJax.startup.adaptor;
const html = MathJax.startup.html;
//  Remove the stylesheet
adaptor.remove(html.outputJax.chtmlStyles);
//  Output the resulting HTML
fs.writeFileSync(r, adaptor.doctype(html.document) + adaptor.outerHTML(adaptor.root(html.document)));
});
}));

我得到错误：

mathjax.js:34
MathJax.startup.promise.then(() => {
^
TypeError: Cannot read property 'then' of undefined

我正在使用https://github.com/mathjax/MathJax-demos-node和MathJax-src作为参考，但我似乎仍然搞不清楚。

编辑：我还没有弄清楚如何在node.js上获得自定义扩展，但这是最新的进展：

import { readFileSync, writeFileSync } from 'fs';
import glob from 'glob';
import { mathjax } from 'mathjax-full/js/mathjax.js';
import { TeX } from 'mathjax-full/js/input/tex.js';
import { CHTML } from 'mathjax-full/js/output/chtml.js';
import { liteAdaptor } from 'mathjax-full/js/adaptors/liteAdaptor.js';
import { RegisterHTMLHandler } from 'mathjax-full/js/handlers/html.js';
import { AllPackages } from 'mathjax-full/js/input/tex/AllPackages.js';
import { Loader } from 'mathjax-full/js/components/loader.js';
import 'mathjax-full/js/util/entities/all';
MathJax = {
config: {
loader: {
paths: { custom: '.' },
require: require,
load: { '[+]': ['[custom]/xypic.min.js'] },
failed: err => console.log(err)
}
},
loader: Loader
};
MathJax.loader.ready('xypic').then(() => {
glob('**/*.html', { "ignore": ['node_modules/**/*.html'] }, (_, res) =>
res.forEach(r => {
const htmlfile = readFileSync(r, 'utf8');
// Register the HTML handler
const adaptor = liteAdaptor();
RegisterHTMLHandler(adaptor);
// Create a MathJax document
const tex = new TeX({ packages: AllPackages.concat('xypic'), inlineMath: [['$', '$']] });
const chtml = new CHTML();
const html = mathjax.document(htmlfile, { InputJax: tex, OutputJax: chtml });
// Typeset the document
html.render();
//  Remove the stylesheet
adaptor.remove(html.outputJax.chtmlStyles);
//  Output the resulting HTML
writeFileSync(r, adaptor.doctype(html.document) + adaptor.outerHTML(adaptor.root(html.document)));
}));
}, err => console.log(err));

奇怪的是，它什么都没做。

Answer 1

似乎MathJax.startup.promise只能在MathJax.startup.ready()中使用
请参阅此处的文档。

尝试：

MathJax.startup = {
ready() {
MathJax.startup.defaultReady();
MathJax.startup.promise.then(() => {
const adaptor = MathJax.startup.adaptor;
const html = MathJax.startup.html;
//  Remove the stylesheet
adaptor.remove(html.outputJax.chtmlStyles);
//  Output the resulting HTML
fs.writeFileSync(r, adaptor.doctype(html.document) + adaptor.outerHTML(adaptor.root(html.document)));
});
}
};