Understanding pure functions in Haskell with IO

Question

Given the meaning of Halkell (edit per Rein Heinrich comment ) f:

f :: IO Int
f = ... -- ignoring its implementation

Quote: “Type-driven development with Idris,”

The key property of a pure function is that the same inputs always give the same result. This property is called referential transparency.

Is f, and, namely, all functions IO ...in Haskell pure? It seems to me that they have not since, lookInDatabase :: IO DBThingwill not always return the same value, since:

• at t = 0, the database may not be available
• at t = 1, the database can be up and return MyDbThingwill lead to

In short, is the function f(and IO ...generally) pure? If so, please correct my misunderstanding, given my attempt to refute functional purity fwith my examples t=....

Answer 1

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Answer 2

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...

main =
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Answer 3

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Answer 4

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