Comment by bmacho

> I'm not sure that's entirely true (I wrote the examples)

Which part?

> the point I'm trying to make is that you can precisely describe what `doSomething` consumes and produces (because it's pure)

I think you failed to demonstrate it, and more or less demonstrated the opposite of it: the type signature of doSomething does not show its implicit dependence on getResult.

In Haskell you can do

  foo :: Int
  foo = 5

  bar :: Int
  bar = foo + 1

(run it: https://play.haskell.org/saved/hpo3Yaef)

which your example does. In this example bar's type signature doesn't tell you anything about what bar 'consumes', and it doesn't tell you that bar depends on foo, and on foo's type. Also you have to read the body of bar, and also it is bad for code reuse.