willemneal / typescript_example

Simple project with example code about TypeScript

Simple TypeScript example

• src - has the TypeScript source files
• dist - where javascript that TypeScript "compiles" to go.
• node_modules - where the npm packages are installed to.
• package.json - file that defines the package
• tsconfig.json- file that with options for typescript's compiler

package.json

"devDependencies": {
  "@types/node": "^10.12.21",
  "ts-node": "^8.0.2",
  "typescript": "^3.3.1"
}

The dependencies needed to create the final package.

"scripts": {
  "build": "tsc",
  "watch": "tsc -w",
  "example": "ts-node src/index.ts"
},

• npm run build compiles the TypeScript in src and puts it dist.
• npm run watch will recompile when a file changes.
• npm run example compiles and runs TypeScript file src/index.ts.

tsconfig.json

{
   "compileOnSave": true,  <-- editors with typescript support will recompile on save
   "compilerOptions": {
       "module": "commonjs",
       "lib": ["es6", "dom"],
       "noImplicitAny" : false, <--- Example option for how strict the compiler is
       "outDir": "dist",        <--- Where to put the output files
       "declaration": true,     <--- Creates '.d.ts' file, which define the types of the generated javascript
       "target": "es5"          <--- Which version of EMCAScript to compile to.
   },
   "include": [  <-- files to becompiled
    "src/**/*"
  ]
}

Setup

To get started install the needed packages with npm install.

Run code

To run a javascript file:

node dist/index.js

or to compile and run the TypeScript, install ts-node globally. npm install -g ts-node

ts-node src/index.ts

Note ts-node is installed in node_modules, so it can be used in the scripts section of the package.json, or called directly,

node_modules/ts-node/dist/bin.js src/index.ts