Very interesting flip! For much of his life, Dijkstra opposed functional programming. He even more strongly criticised FP from Backus and APL from Iverson, which are both very funcional/function-level.
As he said, Java is a mess and any sensible person would oppose the switch from Haskell to Java. I am almost sure he never used any of them. Might have read about them, but highly doubt he run any on computer.
As for the high-level status of Haskell and APL — both languages are very mathematical. Haskell goes very into the abstract realm of computation, while APL tackles very raw form of computation. Semantically, Haskell is way more high-level. In terms of economy of notation and unified concepts, APL has no match.
The most used (by me) Vector package has boxed (efficient) and unboxed (J-like) arrays. With these arrays having map, fold, scan, fromList/toList, zip and unzip combinators, one can have as terse (in the operator count sense) notation as one wishes for.
> Might have read about them, but highly doubt he run any on computer.
Nice goalpost shifting. Anyways, you also neglected that he was a major proponent of structured programming and the author of the letter "Go To Statement Considered Harmful". The idea that he would oppose high-level languages is not based in reality. Specific languages, yes, but not because they are high-level as your silly original comment claimed.
Dijkstra was highly influential in theoretical (proofs, algos) and practical (spec&compiler for Algol60) compuper science. But in reality he used his fountain pen disproportionately more than the computer.
As he said, Java is a mess and any sensible person would oppose the switch from Haskell to Java. I am almost sure he never used any of them. Might have read about them, but highly doubt he run any on computer.
As for the high-level status of Haskell and APL — both languages are very mathematical. Haskell goes very into the abstract realm of computation, while APL tackles very raw form of computation. Semantically, Haskell is way more high-level. In terms of economy of notation and unified concepts, APL has no match.