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then-catch vs try-catch​

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Prettier comment alignment​

It can't be done in prettier, since the developers consider it as a sophisticated task, and also not consistent with their option philosophy.

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Excel Select​

Since there are too many excel packages, not unified, unknown problems, I decided to not use excel.

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After all, to them, using excel or not, doesn't differ too much. But to me, not.

TODO: Database Select: node-sqlite3, better-sqlite3, typeorm, prisma​

A wonderful and respective thing the typeorm did, is to provide developers with a clarified, transparent, and full api, which is hardly to see in prisma or so packages.

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At least, from my own experience, the prisma is even still hardcoding their database query status, which seems unacceptable for those like me to develop a robust application.

[ERR_REQUEST_ESM]​

If your code copied from some place using require, and you can't run it now out of ERR_REQUEST_ESM, it doesn't mean the code is wrong but maybe mean it's written in the node v2 times.

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And now, the simplest remedy you can use is to change all the require into import like this:

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And change the file extension from .js to .mjs, then things is ok: picture 34

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cjs 和 mjs 不要混用​

目前我经过测试，已经充分认识到 cjs 和 mjs 的不可调和矛盾了，甚至 babel 也不方便解决这个问题。

接下来要注意两点，第一点就是代码导入时require和import不要混用，第二点也是最关键的一点，那就是对每个新包要确认一下它是否加了"type": "module"的属性，尤其是 webpack 的那些包，基本都是 full ESM 的...对 Electron 极其不友好。。。

babel 的失败尝试​

babel src --no-babelrc --out-dir lib/es --extensions '.ts,.tsx' --ignore '**/*.spec.ts' --config-file ./.babelrc.es
// ./.babelrc.es
{
  "ignore": ["node_modules/**/*"],
  "presets": [
    ["@babel/preset-typescript"],
    [
      "@babel/preset-env",
      {
        "loose": true,
        "modules": false
      }
    ],
    "@babel/preset-react"
  ],
  "plugins": [
    "@babel/plugin-proposal-class-properties",
    "babel-plugin-add-module-exports",
    "@babel/plugin-transform-classes"
  ]
}

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database-orm: prisma vs typeorm​

interface vs abstract class​

It's very interesting to see how different is between an interface and an abstract class.

For me, the project of hjxh_express_match, interface is enough, and provides me more advantage in running since they are workded ony in compile stage.

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eslint catch/then/return​

In fact, it's a pipe, just like case, which I know it until today.

So, we must return something in catch/then, in order not to goto next pipe.

Also, put then before catch is sometimes good since catch can capture the error caused by inner of then.

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Finally, I wrote like this (with eslint 'no-useless-return': 'off' disabled): picture 8

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Avoid hardcoding of Prisma Error codes​

I first followed the official documentation, and reviewed the section of error codes, however didn't get any message on how to import them except hard coding.

And then I searched the source code, but in vain:

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And its' shocking to me that I even couldn't find the P2002 error since it's the error of duplicate id, which captured by my programme.

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Whereas, I can find such as P1003, and no exception: without P1000 and other P100X codes.

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And finally I tried to search in the github issues.

At first, I got nothing.

Then I use is:issue in:title code, and then quickly find one which is what I am expecting to.

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But it's so sad that no reply on this issue.

I added one comment then.

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Enum or Union / Array​

for literal const (like redux):

export const Ping = 'Ping';
export type Ping = typeof Ping;

export const RequestSelectFile = 'RequestSelectFile';
export type RequestSelectFile = typeof RequestSelectFile;

export const RequestReadFile = 'RequestReadFile';
export type RequestReadFile = typeof RequestReadFile;

export type Channels = Ping | RequestSelectFile | RequestReadFile;

for iterating:

const buttonStatus = ['HIDDEN', 'ENABLED', 'DISABLED'] as const;
// Notice that the array and type can have the same name if you want
type ButtonStatus = typeof buttonStatus[number];

for switch

// Union types
switch (key) {
  case 'HIDDEN': return ...;
  case 'ENABLED': return ...;
  case 'DISABLED': return ...;
  // Notice that there's no default case
}

// Enums
switch (key) {
  case ButtonStatus.HIDDEN: return ...;
  case ButtonStatus.ENABLED: return ...;
  case ButtonStatus.DISABLED: return ...;
  default: return ...;
}

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for...of or .forEach​

The main debate is that for...of is a 'loop', while forEach is a 'iteration', which seems faster since it can be parallel.

Although I prefer for...of since I learned it from python and C11.

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