RFC: a backend-only version about entropy

[ocramz]

Do I understand correctly that the impl(ghcjs) || os(ghcjs) in the library stanza of the .cabal file makes it so that the JS dependencies are not active when the compiler is not GHCJS?

library
  ghc-options:  -O2
  exposed-modules: System.Entropy
  if impl(ghcjs) || os(ghcjs)
    other-modules: System.EntropyGhcjs
  else {
    if os(windows)
      other-modules: System.EntropyWindows
    else {
      other-modules: System.EntropyNix
    }
  }
  other-extensions:    CPP, ForeignFunctionInterface, BangPatterns,
                       ScopedTypeVariables
  build-depends:       base >= 4.8 && < 5, bytestring

  default-language:    Haskell2010

  if impl(ghcjs) || os(ghcjs) {
    build-depends:     ghcjs-dom >= 0.9.5.0 && < 1
                     , jsaddle
  }

[TomMD]

Yes, that's right.