Comment by bad_user | Hacker News Reader

Comment by bad_user | Hacker News Reader

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That's kind of a false dichotomy, as these languages are applied to different problems.

Speaking of the garbage collector, it was the biggest productivity boost that software developers ever experienced and no matter how many tricks the Rust compiler pulls, the hit on productivity is real. And in terms of the "if it compiles, it runs" feeling, that comes with having an advanced type system. Rust pulls some really nice tricks, but cannot match Haskell. And again, the lack of a GC means the compiler's budget is spent on ensuring that the code is memory-safe, with other things having much lower priority.

> Rust pulls some really nice trick, but cannot match Haskell.

I'm not convinced that's true. Rust is even stricter than Haskell in many respects (first example that comes to mind is incomplete pattern matches, which is a compiler error in rust) and strictness also avoids some run-time errors. I've managed to produce infinite loops in Haskell by accidentally defining recursive values more than once.

While I agree with you about pattern matches in Haskell but for completeness sake there is a ghc flag -W for it. If you compile this code with that flag, you will see the result below:

  --hello.hs
  f mx = case mx of
        Just x -> x
        --Nothing -> "NA"

  main = do
    let v = Just "5"
    putStrLn $ f v

  ghc -W hello.hs
  [1 of 1] Compiling Main             ( hello.hs, hello.o )
  hello.hs:1:8: Warning:
    Pattern match(es) are non-exhaustive
    In a case alternative: Patterns not matched: Nothing

In my opinion, incomplete pattern matches should be an error not a warning, but it seems strange to choose a different language based on that issue.

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