Transform .travis.yml to JSON and build Nix from it

.travis.yml

@@ -1,23 +1,30 @@
-language: haskell
-ghc:
-  - '8.8'
-  - '8.6'
-  - '8.4.3'
-  - '8.2.2'
-  - '8.0.2'
-before_install:
-  - sudo apt-get update -qq
-  - sudo apt-get install -qq libgl1-mesa-dev libglu1-mesa-dev freeglut3-dev
-script: cabal new-build all
-install: skip
+{
+  "language": "haskell",
+  "ghc":
+    [ "8.8.3"
+    , "8.6.5"
+    , "8.4.3"
+    , "8.2.2"
+    , "8.0.2"
+    ],
+  "before_install":
+    [ "sudo apt-get update -qq"
+    , "sudo apt-get install -qq libgl1-mesa-dev libglu1-mesa-dev freeglut3-dev"
+    ],
+  "script": "cabal new-build all",
+  "install": "skip",
 
-deploy:
-  provider: hackage
-  username: turion
-  password:
-    secure: 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
-  on:
-    repo: turion/rhine
-    tags: true
-    condition:
-      - $TRAVIS_HASKELL_VERSION = 8.2.2
+  "deploy":
+    { "provider": "hackage"
+    , "username": "turion"
+    , "password":
+      { "secure": "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"}
+    , "on":
+      { "repo": "turion/rhine"
+      , "tags": "true"
+      , "condition":
+        [ "$TRAVIS_HASKELL_VERSION = 8.2.2"
+        ]
+      }
+    }
+}

nix/all-ghcs.nix

@@ -0,0 +1,8 @@
+{ nixpkgs ? import <nixpkgs> {} }:
+
+let
+  travisJobGHCEnvs = (builtins.fromJSON (builtins.readFile ../.travis.yml)).ghc;
+  getGHCVersionFromEnv = env: builtins.concatStringsSep "" ["ghc" (builtins.replaceStrings ["."] [""] env)];
+  supportedGHCVersions = builtins.map getGHCVersionFromEnv travisJobGHCEnvs;
+  buildRhineWith = version: import ../default.nix { compiler = version; };
+in builtins.map buildRhineWith supportedGHCVersions