As "A Brief, Incomplete, and Mostly Wrong History of Programming Languages" put it:
1990 - A committee formed by Simon Peyton-Jones, Paul Hudak, Philip Wadler, Ashton Kutcher, and People for the Ethical Treatment of Animals creates Haskell, a pure, non-strict, functional language. Haskell gets some resistance due to the complexity of using monads to control side effects. Wadler tries to appease critics by explaining that "a monad is a monoid in the category of endofunctors, what's the problem?"
It's a funny joke (I love that post), but it's mostly for people looking from outside in. It says nothing about actually doing IO with Haskell using monads, which is practical and done, and not particularly difficult.
Yeah as long as you understand how to use monads IO is easy.
This is why Haskell tutorials tend to have 100 pages of dense type-theory before getting to “hello world”, while other languages have that on the first page.
Yeah, but that's not because the first 127 pages are "dense type theory". It's because that's the first time it teaches about compiled programs rather than the REPL. Besides, "Hello world" also appears on page 14.
This is simply untrue. You can do IO without understanding what a monad is, simply taking it as "there is this keyword and this syntax I need to use".
No Haskell tutorials that I know of take long to reach "hello world", which is in fact a shorter program in Haskell than in some mainstream programming languages.
