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Re:Algebraic Data Types by seanmcdirmid on Thursday July 31, 2014 @09:32PM (#8117995)
Most type theorists reject that dynamic typing is meaningful and not a misnomer, hence Noel Welsh's assertion that Python has only one type. It doesn't start the conversation off very well.
Re:Algebraic Data Types by tel on Friday August 01, 2014 @07:45PM (#8123441)
I don't think anyone argues that Python has more than one (static) type. It however has a dynamic type system. Significantly, static types and dynamic types do not behave the same way and their corresponding theories have somewhat minor overlap.

In particular, many things I can state about static types do not carry over to dynamic types and visa versa.

I believe many conversations get derailed early because among static type researchers, static types are known merely as "types" and dynamic types as "tags" or "classes". There are meaningful ways to compare these two kinds of things but somehow or another they ought to have different words since confusing the concepts will inhibit understanding quite severely.

Re:Algebraic Data Types by dllthomas on Thursday July 31, 2014 @09:35PM (#8118006)
Did you mean that to be a restatement of what tel said? It seems to be.
Re:Algebraic Data Types by seanmcdirmid on Thursday July 31, 2014 @10:26PM (#8118130)
All but the "if we just listened to each other, we'd understand each other." The type theorist's and programmer's different perspective s means basically that we'd fight over the meaning of type for our entire conversation.
Re:Algebraic Data Types by dllthomas on Friday August 01, 2014 @10:06AM (#8119841)
It wasn't "if we listened", but "if we normalized terms". I agree that getting people to normalize terms with the aim of successfully communicating can be difficult...