ECMAScript module equivalent of CommonJS module usage: const x = require('myModule')(options);

A common, concise idiom of CommonJS modules that export factory functions is:

const instance = import('myModule')(myOptions);

This is concise and minimizes consumption of the name space.

With ECMAScript modules and the import declaration, the same or similar is not possible because the import declaration is not an expression that returns a value and it must be at the top level of the module: they cannot be within a block or function, including an immediately invoked function expression (IIFE).

Assuming the module in question exports a factory function as its default export, then the nearest equivalent would be something like:

import myFactory from 'myModule';

const instance = myFactory(myOptions);

If a named export the something like:

import { exportName as myFactory } from 'myModule';

const instance = myFactory(myOptions);

This is a little less concise: two lines of code instead of one, and an additional name consumed in the module name space. But otherwise gives the same result.

Something more equivalent is possible with the dynamic import keyword. This is function-like and can occur within a function, including an IIFE.

const instance = (await import('myModule')).default(myOptions);

This is only a little less concise than the CommonJS syntax. Similar construct is possible with named exports, by simply replacing 'default' with the name of the named export.

Using dynamic import keyword instead of the import declaration, one gives up the static analysis made possible by the import declaration, and there may be other benefits of the declaration over the keyword.

JavaScript testing with Tape

 I mostly use tape for testing my JavaScript packages. Today I was updating dependencies and update of tape was among them.

The link from npmjs.com to GitHub was broken, yielding a 404 page. So I logged an issue and within a few minutes the links were fixed.

So, the GitHub repository for tape has moved to https://github.com/tape-testing/tape but all is well. Jordan is still actively maintaining the package.

It remains my favourite test package for JavaScript.

First release from the current repository was Nov 26, 2012. Well over a decade ago. It is good to see that it is still maintained and with attention to backwards compatibility.

Thus far, all my packages are CommonJS.

For linting, I use eslint with configuration @ig3/eslint-config-entrain. 

For coverage, I use c8.

For test runner I use multi-tape. Pending an update of multi-tape dependencies, I have published @ig3/multi-tape.

Typical test script is: "eslint . && multi-tape test/*.js"

@ig3/eslint-config-entrain is based on neostandard and eslint version 9. Typical eslint.config.js is:

 

'use strict';

const eslintConfigEntrain = require('@ig3/eslint-config-entrain');

module.exports = [
  ...eslintConfigEntrain,
];

Or sometimes something like:

'use strict';

const eslintConfigEntrain = require('@ig3/eslint-config-entrain');

module.exports = [
  ...eslintConfigEntrain,
  {
    ignores: ['public/js/**'],
  },
];

Setup is:

$ npm install -D @ig3/eslint-config-entrain c8 tape multi-tape

 Change the test script to:

"eslint . && c8 multi-tape test/*.js"

 And create eslint.config.js as above.

 

Thunar sort order

For many years I have run Debian with xfce4 desktop.

I have always hated the way Thunar sorts files by name. The developers would say it is not a Thunar issue but rather a Gtk issue. But I really don't care. I hate it whatever the root cause. It is made worse by the fact that there is absolutely no configuration possible other than collation options (LC_ALL and LC_COLLATE) but these don't fix the problem.

So, today I dug in to fix it.

I tried several other file browsers, but they all have slight variations of the same nonsense and I didn't find any that sort file names sensibly (e.g. like ls does).

There are many bug reports against Thunar, Nautilus and several others, reporting that available sorting options are not satisfying.

There are so many, it makes me wonder why there isn't a simple plug-in option, to separate sorting from other aspects of the file browser, allowing people to easily develop the sorting algorithm they need. Gtk could provide this but so could the various file browsers. It seems all I investigated in any detail delegate sorting to Gtk and refuse to add any features to work around its limitations and stupidity (i.e. 'natural' sorting).

I read many bug reports and posts, with the conclusion that there is no configuration option to fix it.

I tried building Thunar from source, thinking I would hack on it to fix the sorting or add an interface to an external sort implementation, but there were too many dependencies and I got tired of installing them.

But in reading through all the bug reports, I came across GlibSortFileNameHackLibrary so I gave it a try. I cloned the repo and tried to build it.

On Debian Bookworm, despite having built various other packages, I still had to install libglib2.0-dev:

$ sudo apt install libglib2.0-dev

Then:

$ make all

This terminates with an error compiling test.c, but that's only a test program. The library builds OK.

Then, from a command window:

$ thunar -q; LD_PRELOAD=./glibSortFileNameHack.so thunar

This launched a new Thunar instance and files were sorted sensibly (as opposed to the Gtk idea of 'naturally'). It was wonderful! Finally, I can find files in Thunar without wasting time scrolling up and down to try to figure out where they have been misplaced.

I couldn't find trace of a Thunar background process running after I logged in (i.e. ps -ef showed nothing with 'thunar' in the command line). So I guessed there isn't one and didn't worry about why.

I use Whisker menu but don't really know how to configure it. When I tried prefixing the command for the file browser launcher with LD_PRELOAD=/path/to/glibSortFileNameHack.so, I got an error that LD_PRELOAD isn't executable. 

So, I made a bash script:

#!/bin/bash
LD_PRELOAD=/home/ian/lib/glibSortFileNameHack.so thunar

And I changed the launcher to run the script.

This seems to work fine. At least, I haven't noticed any problems yet.

Now every Thunar instance sorts files sensibly.

Kudos to Alexandre Richonnier for publishing GlibSortFileNameHackLibrary. It hasn't been updated in 9 years, but it still works a treat!

@ig3/srf - Spaced Repetition Flashcards

It is 2 years since I gave up on Anki and wrote @ig3/srf.

I have used it to study almost very day, for 2 years now. I have changed the scheduling algorithm several times. Sometimes little tweaks of parameters and sometimes fundamental changes to the algorithm.

The most recent big change was to eliminate the percentage of correct answers as a factor in calculating the new interval. Instead, for each review of a card with interval longer than the learning threshold, the interval and due date of every card with interval longer than the learning threshold is adjusted, according to the difference between percent correct and the target percent correct. This decreases the delay of feedback. It's early days, but it seems to be working.

Overall I am very pleased with @ig3/srf. I am limited by my poor memory but not overwhelmed and not feeling like a failure. At least, not most days. There are some days, usually after a few days without sleep, that it truly seems hopeless. But then I get some rest and get back on track.

I have put a lot of time into development @ig3/srf over the past two years, but I am confident that it was less effort for a better outcome than trying to maintain my Anki plugin to improve Anki's algorithm. I don't regret my decision at all.

apt update failing with connection failed

Today, attempting apt update was failing:

Hit:1 http://deb.debian.org/debian bullseye InRelease
Err:2 http://security.debian.org/debian-security bullseye-security InRelease
  Connection failed [IP: 151.101.166.132 80]
Err:3 http://deb.debian.org/debian bullseye-updates InRelease
  Connection failed [IP: 151.101.166.132 80]
Reading package lists... Done
Building dependency tree... Done
Reading state information... Done
All packages are up to date.
W: Failed to fetch http://deb.debian.org/debian/dists/bullseye-updates/InRelease  Connection failed [IP: 151.101.166.132 80]
W: Failed to fetch http://security.debian.org/debian-security/dists/bullseye-security/InRelease  Connection failed [IP: 151.101.166.132 80]
W: Some index files failed to download. They have been ignored, or old ones used instead.

I was able to access the resources in my browser, which was redirected to https.

So I updated /etc/apt/sources.list, changing http to https throughout and then apt update completed without errors.

Hit:1 https://deb.debian.org/debian bullseye InRelease
Get:2 https://deb.debian.org/debian bullseye-updates InRelease [44.1 kB]
Get:3 https://security.debian.org/debian-security bullseye-security InRelease [48.4 kB]
Get:4 https://security.debian.org/debian-security bullseye-security/main Sources [192 kB]
Get:5 https://security.debian.org/debian-security bullseye-security/main amd64 Packages [236 kB]
Get:6 https://security.debian.org/debian-security bullseye-security/main Translation-en [154 kB]
Fetched 675 kB in 5s (138 kB/s)                            
Reading package lists... Done
Building dependency tree... Done
Reading state information... Done
68 packages can be upgraded. Run 'apt list --upgradable' to see them.

The original sources had been working for well over a year. It seems http is no longer supported.

@ig3/couchapp is deprecated

 @ig3/couchdb is deprecated.

It works with CouchDB 3.x but vhost and rewrite rules are deprecated and planned to be removed from CouchDB 4. Without them, couchapps will not work.

The primary feature of a couchapp is that it is served from a CouchDB server. No other server is required.

The concept of a CouchApp arose with CouchDB. But, as the CouchDB docs indicate, CouchApps are deprecated:

Note: Previously, the functionality provided by CouchDB’s design documents, in combination with document attachments, was referred to as “CouchApps.” The general principle was that entire web applications could be hosted in CouchDB, without need for an additional application server.

Use of CouchDB as a combined standalone database and application server is no longer recommended. There are significant limitations to a pure CouchDB web server application stack, including but not limited to: fully-fledged fine-grained security, robust templating and scaffolding, complete developer tooling, and most importantly, a thriving ecosystem of developers, modules and frameworks to choose from.

The developers of CouchDB believe that web developers should pick “the right tool for the right job”. Use CouchDB as your database layer, in conjunction with any number of other server-side web application frameworks, such as the entire Node.JS ecosystem, Python’s Django and Flask, PHP’s Drupal, Java’s Apache Struts, and more.

Several tools have been written to automate building and deploying CouchApps. The earliest I know about were developed by Chris Anderson. Some history is available in the post: What is Couchapp?.

I had been using a node based implementation of the couchapp tool but when I set up a new CouchApp early 2022 I found it no longer worked. I forked it and released @ig3/couchapp but learned that CouchDB had deprecated the features that make CouchApps possible.

So I rebuilt my CouchApp / couchapp based apps using a combination of nginx and CouchDB.

It isn't hard.

Everything comes from nginx:

 * static content is served by nginx directly

 * CouchDB access is proxied by nginx

 * Rewrite rules are written in nginx

 A very simple app might be configured in nginx as:

server {
  server_name mycoucnapp.example.com;
  listen 443 ssl http2;

  client_max_body_size 8M;

  location / {
    root /usr/local/data/mycouchapp/attachments;
    try_files $uri /index.html;
  }

  location /couchdb {
    proxy_pass http://localhost:5984/;
  }
  location /couchdb/ {
    proxy_pass http://localhost:5984/;
  }
}

Note the trailing slashes on the URLs to proxy_pass. They are 
significant. Without them, the entire request path is passed to CouchDB.
With them, the / replaces the location (/couchdb or /couchdb/). 

How I study Chinese

 Just a few notes on how I study Chinese.

I study daily using Spaced Repetition Flashcards (a.k.a. srf). About an hour per day.

I started using Anki, but I found the algorithm didn't work for me, causing me to become overwhelmed with big backlogs that I couldn't get through and I had to manually adjust new cards. The algorithm of srf works better for me and it regulates new cards automatically.

But there are many programs for presenting flashcards and any of them can work.

Because I started with Anki, I started with a few Anki decks. One of characters, one of Chinese provinces and cities, and one of words and sentences. I have added many of my own cards, mostly from videos I have watched.

I find the sentences harder to learn initially but easier in the long term. Individual characters are too abstract, with too many unrelated meanings. As I progress, it seems more important and more effective to be able to recognize them in the context of words (combinations of two or more characters) and sentences. Even if I knew all the meanings related to each individual character, it often leaves me unsure about the meaning of a word or sentence or, worse, with the wrong interpretation.

I watch a lot of Chinese videos with English and Chinese subtitles. Mostly modern drama with, I hope, modern vocabulary and accent.

A few years ago, when I started, I had a lot of difficulty finding good videos with clear audio and good subtitles. More recently there is a lot of good content. YouTube has many channels of good content. More than I can watch. I sometimes watch videos from Chinese sites, but many of them aren't available to me or require setting up accounts, so I don't bother. There's enough content on the free sites.

I have begun reading. I use Calibre to maintain a library of epub books but I view them in my Firefox browser using calibre-web to serve them and the @ig3/zhongwen add-on for lookup of Chinese characters.

The @ig3/zhongwen add-on is available from the Firefox add-ons website.

I use @ig3/zhongwen rather than the Zhongwen add-on because @ig3/zhongwen supports lookup of content in iframes and calibre-web presents the epub content in iframes, so the Zhongwen add-on doesn't work. I have also improved the positioning of the pop-up in @ig3/zhongwen so it doesn't cover the selected characters.

With a local Calibre library and calibre-web running on my laptop, I can read Chinese with character lookup even when I'm offline.

I'm old. My memory isn't as good as it used to be. But I am making progress learning Chinese. The stats in srf make this clear and also, when I watch videos or listen to conversations of native Chinese speakers, I can't yet follow but I begin to catch words and phrases and understand them without consciously translating them. It's always a thrill when I clearly get the meaning without having to think about it.

I only use Firefox, not Chrome, Safari, Opera or any other browser. While calibre-web might work from other browsers, I haven't tried and don't intend to support using @ig3/zhongwen from other browsers.  In particular, I have not published it as a Chrome add-on, as the original Zhongwen add-on is. I have submitted a patch to the Zhongwen add-on maintainer, for support of content in iframes, but have had no response to it and it hasn't been merged. Since then, I have made several more changes to @ig3/zhongwen, including a revision of how iframes are supported, making support more reliable.

I also produce my own epub documents for study. I first put the text into Markdown files then I use a simple script to convert collections of Markdown files (one per chapter) into an epub file that I can load into my Calibre library and review with calibre-web and the @ig3/zhongwen add-on.

There's plenty of Chinese content on the Internet, including many books and novels available as epub documents or easily converted to epub documents. The @ig3/zhongwen add-on doesn't work directly on all sites. Some don't allow selection of text at all. I also find it convenient to be able to review when I'm offline, which I can do if I have copied the text to make my own epub documents. A little collection that I can review as many times as I need to.

While @ig3/zhongwen is easy and very helpful, its definitions don't always help and miss the broader context. Sometimes, for example, I don't know how to break down a sentence into the correct words and phrases. While it is probably obvious to a Chinese person, I often find that there are several overlapping possibilities. I find Google Translate very helpful for understanding the meaning and structure of whole sentences.

With Google Translate, what I sometimes do is copy in a whole sentence, then split it onto multiple lines in the input box to make sure I am correct about what the words and phrases are.

The MDBG website, from which the dictionary used by @ig3/zhongwen comes, is very helpful, with various lookup functions. 

The stroke diagrams on the MDBG website are great! Though the count of strokes is sometimes nonsense. I think the discrepancies of stroke counts come from MDBG adding up counts of radicals in their traditional forms when the character has them in simplified form, with fewer strokes. Or sometimes simply errors. I try not to get hung up on the stroke counts, but I do try to learn the 'correct' stroke order and direction. Teaching sites for hand writing seem to emphasize stroke order and direction very much.