Typing and Typecheck

Introduction to Functional Programming in Scheme - slide 10 : 49

On this page we will provide a possible overview of different kinds of typing and typecheck

There is no overall and univeral agreement on the definitions of weak/strong/static/dynamic typing

Typed/untyped
- Typed: Operations are only applicable to data of specified types
- Untyped: Any operation can be performed on any type of data
Strong/weak
- Strong: Types are strictly enforced. Operations performed on wrong types of data leads to an error.
- Weak: Values of one type can be treated as values of another type
Static/dynamic
- Static: Type checking is done before the program is executed
- Dynamic: Type checking is done at run-time

Scheme is (relatively) strongly and dynamically typed