Learning TypeScript 2.x - Second Edition

The --strict mode

TypeScript allows us to use the --strict compilation flag to enable all strict type checking options. Enabling --strict enables --noImplicitAny, --noImplicitThis, --alwaysStrict, --strictPropertyInitialization, and --strictNullChecks:

• The --strictNullChecks compilation flag enables non-nullable types.
• The --noImplicitAny flag forces us to explicitly declare the type of a variable when the type inference system is not able to automatically infer the correct type.
• The --alwaysStrict flag forces the TypeScript parse to use the strict mode.
• The --noImplicitThis flag forces us to explicitly declare the type of the this operator in functions when the type inference system is not able to automatically infer the correct type.