What are some examples of type checking in programming languages?

What are some examples of type checking in programming languages?

Type checking is a mechanism to ensure that variables are used consistently with their data types. Examples include:

1. Static Type Checking: Languages like Java and C++ check types at compile time.
2. Dynamic Type Checking: Languages like Python and JavaScript check types at runtime.
3. Strong vs Weak Typing: Strongly typed languages like Haskell enforce strict type rules, while weakly typed languages like JavaScript allow more flexibility.

Can you explain the difference between static and dynamic type checking?

Sure! Static type checking occurs at compile time, meaning errors are caught before the program runs. This can lead to safer code but requires more upfront definition of types. Dynamic type checking, on the other hand, occurs at runtime, allowing for more flexibility but potentially leading to runtime errors if types are misused.

What are the advantages of using static type checking?

The advantages of static type checking include:

1. Early Error Detection: Catches type errors during compilation.
2. Improved Performance: Optimizations can be made since types are known at compile time.
3. Better Documentation: Type annotations serve as documentation for code, making it easier to understand.

Are there any languages that support both static and dynamic type checking?

Yes, some languages like TypeScript and Scala support both static and dynamic type checking. TypeScript adds static typing to JavaScript, allowing developers to catch errors early while still enabling dynamic features.