CLEAN Programming Language Help For Students

Clean is a general purpose, state-of-the-art, pure and lazy functional programming language designed for making real-world applications. Clean is based on the concept of mathematical functions. Clean is a pure functional language, there is not such a thing as an assignment. This has a big advantage: a function cannot have a side-effect. A Clean function is referential transparent: the result of a function only depends on the value of the function arguments and on nothing else. Clean functions and the Clean program as a whole (which is a function application) by using traditional mathematical reasoning: uniform substitution and mathematical induction.

This has important consequences:

• Once a function is working, it will always work. A function will always react in the same way, regardless when and in which context the function is used;
• One can reason about

 module hello
 Start :: {#Char}
 Start = "Hello, world!"