TypeScript for Enterprise Applications - Part 2

tsconfig.json is a configuration file for TypeScript projects. It is located in the root folder of a TypeScript project and contains compiler options to compile the TypeScript code..

With the option "strict": true, it ensures strong correctness of a program by enabling these checks:noImplicitAny restricts to define explicit any for a variable.

• noImplicitThis raises error when there is a this is any implicit any.

• alwaysStrict JS "use strict" mode.

• strictBindCallApply restricts bind, call and apply calling underlying function with correct type.

• strictNullChecks restricts using null explicit.

• strictFunctionTypes function parameters to be checked for their types.

• strictPropertyInitialization give value to properties.

• noUnusedLocals stops you using unused local variables.

• noUnusedparameters restricts you using unused parameter with prefix "_"

• noImplicitReturns restricts return type

• noFallthroughCasesInSwitch returns error if non-empty case doesn't do break or return.

• types specify @types/* packages to be included.

• stripInternal information meant only for internal purposes.

• exactOptionalPropertyTypes It stops using undefined as an optional property.

• noUncheckedIndexedAccess undeclared keys should be assigned to undefined so they won't go unchecked.

• noPropertyAccessFromIndexSignature property should be accessed using the "[]" syntax and not the "." syntax.

• noImplicitOverride should specify 'override' explicitly.

• allowSyntheticDefaultImports allow commonJS module as ESM module.

• esModuleInterop manages interoperability of ESM and CJS.

• skipDefaultLibCheck stops breaking changes from node_modules.

• useUnknownInCatchVariables errors caught will be promoted to unknown instead of any.