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// https://github.com/Microsoft/TypeScript/wiki/What's-new-in-TypeScript

type MyRecord = Record<string, number>
type MyRecord = { [key: string]: number }

// TODO improved enums!
const OPERATORS = [ '*', '/', '+', '-' ] as const
type Operator = typeof OPERATORS[number]

type Color = "primary" | "secondary" | (string & {});

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https://glthr.com/XML-fundamental-to-Claude

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// https://code.claude.com/docs/en/settings
{
  "$schema": "https://json.schemastore.org/claude-code-settings.json",
  "permissions": {
    "allow": [
      "Bash(npm run lint)",
      "Bash(npm run test *)",
      "Read(~/.zshrc)"
    ],
    "deny": [

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Resources for learning JavaScript (and its ecosystem) in 2020

• Links are introduced in suggested order of reading
• Intended target: someone knowing to program but not in JavaScript

Why?

1. Why investing in JavaScript? BLOG POST IN PROGRESS

Fundamentals

1. A re-introduction to JavaScript (JS tutorial) https://developer.mozilla.org/en-US/docs/Web/JavaScript/A_re-introduction_to_JavaScript

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## https://developers.google.com/edu/python

# ternary
a if x else b

## strings
## https://developers.google.com/edu/python/strings
s = 'hi'
print(s[1])          ## i
print(len(s))        ## 2

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// null coalescings https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Nullish_coalescing
foo = foo ?? 42
foo ??= 42

// optional chaining https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Optional_chaining
dog?.name
dog?.[name]
hello?.(target)

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// https://react.dev/learn/typescript

import React from 'react'
// really? or import * as React from 'react' ?? https://github.com/facebook/react/pull/18102 ALSO https://www.typescriptlang.org/tsconfig/#allowSyntheticDefaultImports
// or not even need to import React? https://parceljs.org/recipes/react/#jsx
import React, { Component } from 'react'

// (from .d.ts)
type ReactNode =
        | ReactElement

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/////////////////////////////////////////////////
// __dirname, __filename
// https://gist.github.com/sindresorhus/a39789f98801d908bbc7ff3ecc99d99c#pure-esm-package
// https://nodejs.org/api/globals.html
import * as path from 'node:path'
import { fileURLToPath } from 'node:url'

const __dirname = path.dirname(fileURLToPath(import.meta.url))

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/////// REDUCE ///////
res = iter.reduce((acc, val) => {
  return acc + val
}, 0)
err = decorators.reduce((err, decorator) => {
  return decorator(err)
}, err)

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import EventEmitter from 'emittery'

const EMITTER_EVT = 'change'

const emitter = new EventEmitter<{ [EMITTER_EVT]: string }>()

emitter.emit(EMITTER_EVT, `[in-mem]`)
const unbind = emitter.on(EMITTER_EVT, (src: string) => { ... })