Design patterns for composability with traits (i.e. typeclasses)?

[keean]

@shelby3

If you use lowercase for types, then you can't distinguish then from instance (aka variable) names except by context. In C++/Java/Scala, type parameters (aka variables) are usually all uppercase and type names are Camel case with first letter uppercase. Variable (and function/method) names are usually lower case or first letter lower case with Camel case for function names.

I don't disagree with this, but I think I want to distinguish between type variables and types too. Most of my coding does not involve concrete types, so having type variables distinguishable seems better to me.

@shelby3

Not necessarily. Did Python split any existing user base? Ruby's? Rather I think Python identified a niche for readable consistency.

I think they both took users away from Perl There are only so many programmers so new languages must take away from somewhere.

@shelby3

Btw, afaics functional programming can be readable by annotating the code with the types. Afaics, readability can be higher in a functional style, if done well.

Well more different types in an expression is worse, and having to add type annotations is worse. It also doesn't solve the indexing problem, and that is having variables for index lookup is much clearer than maps and folds especially when you have more than one index in play. See my permutations example in JavaScript I posted.