Emphasize importance in FP

[dszakallas]

In functional programming, everything should be a function, because functional programming is about using functions everywhere. If you don’t write functions everywhere you are not a functional programmer. So it is cool that with this module, you can now use a function that returns the value true, instead of using just the value true, which is not functional style. As functional programming is all the hype nowadays, I think you should mention this advantage in your docs.

[mde]

That's an incredibly good point -- immutability and provability are super valuable aspects of FP. Perhaps you could give us a PP that helps explain this for the huge number of users for the true library.