What Is Type Checking?
Type checking is a process performed by a compiler or interpreter to verify the consistency and correctness of types in a computer program.
It ensures that the operations performed on variables, parameters, and function return values are compatible and adhere to the expected data types.
There Are two Main Approaches to Type Checking
- Static Type Checking: In static type checking, the type analysis is performed at compile time, before the program is executed. The compiler examines the program’s source code and checks for type errors based on the declared types of variables, functions, and expressions. Static type checking helps detect type-related errors early in development, improving program reliability and security. It ensures that the program adheres to the specified type rules and prevents potential type mismatches that could lead to runtime errors.
- Dynamic Type Checking: In dynamic type checking, the analysis is performed at runtime, during program execution. The type of a variable or expression is determined dynamically based on its value or the context in which it is used. Dynamic type checking allows for more flexibility, as types can be determined dynamically and can change during program execution. It is helpful in scenarios where types may vary or when dealing with dynamically typed languages where type declarations are not required.
Type checking is essential for catching type-related errors, ensuring program correctness, and improving code quality.
The choice between static and dynamic type checking depends on the programming language, its design philosophy, and the trade-offs between flexibility and early error detection.