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> Haskell won’t let you use a wrong type in a container Could you elaborate? Java should throw a runtime exception for mismatches.

• josephcsible 5y ago
  The key word in your post is "runtime". Haskell will prevent that bug at compile time instead.
  • azth 5y ago
    Actually, I was thinking of covariant arrays. The compiler should prevent issues at compile time for generic collections, same as Haskell.
  • kaba0 5y ago
    That’s false. Java’s generics are sound, you can’t introduce runtime type errors without casting (which is also true of haskell)
    • TheDong 5y ago
      As a pointless pedantic nit, Java's type-system is unsound: https://io.livecode.ch/learn/namin/unsound https://io.livecode.ch/learn/namin/unsound But realistically, the above doesn't matter. What actually matters is that you often _do_ have to cast at runtime in java, so it's somewhat common to hit type errors at runtime in practice. Haskell's type-system makes runtime type casting both less necessary, and vanishingly rare, meaning such runtime cases are practically never hit. The above is at least true from my personal anecdotal experience.
      • kaba0 5y ago
        As far as I know that unsoundness “hack” no longer work. Hm, could you please show me where you had to cast? Long ago, some resource/service lookup did require casting, but my anecdotal experience is that there really is no common area where I have to cast anything anymore.