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I have installed Haskell platform and I have the 7.10.3 version of ghci, which has the 4.8.2.0 version of base. I need to install gloss-1.8.* which needs base-4.7.* version of base.

My question is how to install this older version now, when I already have the newer version. Is it possible? Or do I have to uninstall the Haskell platform and install an older version?

Willem Van Onsem
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Caroso
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    well first of all `gloss-1.8.1.*` needs `base == 4.6`, and `gloss-1.8.2` needs `base == 4.7`, but are you aware that the latest gloss version `gloss-1.10.1.1` needs `base == 4.8.*` which you could use. Now the question is - why do you need this old version of gloss? – epsilonhalbe May 12 '16 at 19:07
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    You can have multiple GHC versions (with their matching base libraries) installed at once. But you should definitely think about whether you really need that exact version. – dfeuer May 12 '16 at 19:15
  • because I found a game in Haskell on the internet, which is created with this version...I want to test it and try to make another starting with this example. Any ideas for my question? – Caroso May 12 '16 at 19:38
  • and how can i install another version? – Caroso May 12 '16 at 19:45
  • You could try editing the game's Cabal configuration to make it use the newer version and see if it works. Sometimes upper bounds go out of date. – dfeuer May 12 '16 at 20:04
  • I'm beginner in Haskell..I'm trying to understand how to make a game ..I don't think I can handle with editing configuration..that's why I'm trying to install an old version of ghc with 4.7.* base – Caroso May 12 '16 at 20:12
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    Coroso also if you are using `cabal` to build, you might try the invocation `cabal install --allow-newer` This permits `cabal install` to use more recent versions than the `.cabal` file does. The syntax is pretty simple btw, you just go into the `.cabal` file and look at the `build-depends` or `Build-Depends` stanza(s), and change each `this_package > 0.7 && < 0.9` to `this_package > 0.7`. You must preserve commas - that's as tricky as it gets – Michael May 12 '16 at 20:37
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    Coroso, oh, and if a range like `gloss-1.8.* ` is given, change it to just `gloss` or `gloss > 1.7` or the like. In fact just doing that *may* work if the other dependencies are ok. – Michael May 12 '16 at 20:45
  • it works. thanks for help – Caroso May 12 '16 at 21:02
  • Is there any reason those knowledgeable about Haskell have refused to answer the question as stated in the title? If not, could you please answer that question? If not, could the author please change the title of the question so as not to mislead people searching for the answer? – user3673 Feb 04 '20 at 18:52

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