What is the purpose of using tsconfig.json file ? (original) (raw)

Last Updated : 16 May, 2022

tsconfig.json file is a file of JSON format which allows us to point the root level files and different compiler options to setup that require to compile a TypeScript based projects. The existence of this file in a project specifies that the given directory is the TypeScript project folder root.

The tsconfig.json file mainly consists of the information for the following:

• CompilerOptions
• CompileOnSave
• Files
• Include
• Exclude

Let's take an example file of tsconfig.json file and understand the purpose of each of its parts.

tsconfig.json `

{ "compileOnSave": true, "compilerOptions": { "module": "system", "noImplicitAny": true, "removeComments": true, "allowUnreachableCode": false, "strictNullChecks": true, "outFile": "../JS/TypeScript/HelloWorld.js", "sourceMap": true }, "files": [ "program.ts", "sys.ts" ], "include": [ "src//*" ], "exclude": [ "node_modules", "src//*.spec.ts" ] }

`

CompilerOptions - It is a property that allows specifying additional options to the TypeScript compiler. Given a list of a few optional settings section of the compilerOptions property that is needed most of the time:

• listFiles
• module
• outDir
• outFile
• rootDir
• sourceRoot
• allowUnreachableCode
• allowJs
• noImplicitUseStrict
• strictNullChecks

{
"compilerOptions": {
"module": "system",
"noImplicitAny": true,
"removeComments": true,
"allowUnreachableCode": false,
"strictNullChecks": true,
"outFile": "../JS/TypeScript/HelloWorld.js",
"sourceMap": true
}
}

CompileOnSave - It is a property that can be used to instruct the IDE to automatically compile the given TypeScript files and generate the output for the same.

{
"compileOnSave": true,
"compilerOptions": {
"module": "system",
"noImplicitAny": true,
"removeComments": true,
"allowUnreachableCode": false,
"strictNullChecks": true,
"outFile": "../JS/TypeScript/HelloWorld.js",
"sourceMap": true
}
}

Files - It is a property that gives a list of TypeScript files that will be included by the compiler. The URL of the files can be both relative or absolute.

"files": [
"program.ts",
"sys.ts"
]

Include - It is a property that allows you to include a list of TypeScript files using the glob wildcards pattern.

"include": [
"src/**/*"
]

Exclude - It is a property that allows you to exclude a list of TypeScript files using the glob wildcards pattern.

"exclude": [
"node_modules",
"src/**/*.spec.ts"
]