Know how to learn the language After all, how can anyone golf in a language they can't use! Online Clean isn't a well-known or well-documented language, and the name certainly doesn't make it easy to find much-needed resources to remedy these issues... or does it? Clean was originally called ...

Forget about character encoding Clean's compiler doesn't care about what encoding you think you've saved the source file as, just about the byte values in the file. This has some neat consequences. In the body of the source code, only bytes with code-points corresponding to the printable ASCII ...

Know your Knodes Some of the strongest constructs (for golfing) in functional languages are let ... in .... Clean of course, has this, and something better - the #. What is a node? Clean's #, and the ubiquitous | (pattern guard) are both known as 'node expressions'. They represent specific nod...

Avoid import StdEnv when possible To access built-in functions, even seemingly basic ones like (==) or map, an import statement is needed, usually import StdEnv because it imports the most common modules like StdInt, StdBool and so on (see here for more info on StdEnv). However it can be possib...

Use shorter lambdas Sometimes you find yourself using a lambda expression (to pass to map, or sortBy, etc.). When you're doing this (writing lambdas), there's the right... and the short way. The right way: This is sortBy, with an idiomatic lambda sorting lists from longest to shortest sortBy ...