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								---
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								categories:
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								  - Programming Languages
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								tags:
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								  - typescript
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								---
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								# Setup and configuration
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								## Installation and configuration
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								TypeScript offers custom installations for most modern JS-based frameworks
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								including Webpack, React.js and Vue.js. The instructions below cover minimal TS
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								set-up outside of a specific framework. TypeScript adds an additional step to
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								any build process since your code must compile to JS before any bundling and
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								transpilation can occur.
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								## Installation
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								```
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								mkdir typescript-project
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								cd typescript-project
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								npm i typescript --save-dev
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								```
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								## Initialise project
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								```
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								npx tsc --init
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								```
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								## Basic configuration
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								```json
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								"compilerOptions": {
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									"target" : "es2020", //es2015 for prod
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									"module" : "es2020",
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								  	"allowJs": true,
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								  	"checkJs": true,
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								  	"strict": true,
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								  	"esModuleInterop": true
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								}
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								```
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								### Specify output paths (for production code)
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								```json
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								"compilerOptions": {
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									...
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									"outDir": "dist",
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									"sourceMap": true,
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								}
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								```
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								### Compile-time commands
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								```
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								tsc --noEmit
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								```
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								```
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								tsc --noEmit --watch
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								```
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								## Global requirements
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								```
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								npm install -g typescript
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								npm install -g ts-node
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								```
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								`ts-node` allows you to run TS files the way you would with standard JS, i.e.
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								`node [filename]`, you just use `ts-node filename` .
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								This is a convenience that saves you compiling from TS → JS and then running
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								Node against the compiled JS. Which is useful for debugging and checking values
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								as you work.
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								## Imports and exports
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								You may wish to define your custom types outside of their application, for
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								instance in a `/types/` directory. The custom type or types can then be imported
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								using standard ES6 imports:
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								```tsx
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								export type Article = {
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									title: string,
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									price: number,
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								}
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								export type AnotherType = {
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								...
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								}
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								```
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								```tsx
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								import { Article, AnotherType } from "./types/allTypes.js";
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								import Article from "./types/allTypes.js";
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								```
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								TypeScript also provides a specific import keyword `type` so that you can
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								distinguish type imports from other module imports. This is handy when you have
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								multiple components in the one file:
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								```tsx
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								import type { Article } from "./types/allTypes.js";
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								```
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