Merge branch 'dev' into topic/webgl

Conflicts:
	.gitignore
	compiler/Generate/JavaScript.hs
	compiler/Parse/Helpers.hs
	compiler/SourceSyntax/Expression.hs

.gitignore

@@ -12,3 +12,4 @@ data
 .DS_Store
 build
 cache
+*~

Elm.cabal

@@ -39,7 +39,6 @@ Library
   Hs-Source-Dirs:      compiler
   other-modules:       SourceSyntax.Declaration,
                        SourceSyntax.Expression,
-                       SourceSyntax.Everything,
                        SourceSyntax.Helpers,
                        SourceSyntax.Literal,
                        SourceSyntax.Location,
@@ -55,6 +54,7 @@ Library
                        Generate.Markdown,
                        Transform.Canonicalize,
                        Transform.Check,
+                       Transform.SafeNames,
                        Transform.SortDefinitions,
                        Transform.Substitute,
                        Transform.Optimize,
@@ -111,7 +111,6 @@ Library
                        text,
                        transformers >= 0.2,
                        union-find,
-                       uniplate,
                        unordered-containers
 
 Executable elm
@@ -120,7 +119,6 @@ Executable elm
   Hs-Source-Dirs:      compiler
   other-modules:       SourceSyntax.Declaration,
                        SourceSyntax.Expression,
-                       SourceSyntax.Everything,
                        SourceSyntax.Helpers,
                        SourceSyntax.Literal,
                        SourceSyntax.Location,
@@ -135,6 +133,7 @@ Executable elm
                        Generate.Cases,
                        Transform.Canonicalize,
                        Transform.Check,
+                       Transform.SafeNames,
                        Transform.SortDefinitions,
                        Transform.Substitute,
                        Transform.Optimize,
@@ -191,14 +190,12 @@ Executable elm
                        text,
                        transformers >= 0.2,
                        union-find,
-                       uniplate,
                        unordered-containers
 
 Executable elm-doc
   Main-is:             Docs.hs
   Hs-Source-Dirs:      compiler
   other-modules:       SourceSyntax.Declaration,
-                       SourceSyntax.Everything,
                        SourceSyntax.Expression,
                        SourceSyntax.Helpers,
                        SourceSyntax.Literal,
@@ -235,6 +232,41 @@ Executable elm-doc
 
 Test-Suite test-elm
   Type:            exitcode-stdio-1.0
-  Hs-Source-Dirs:  tests
+  Hs-Source-Dirs:  tests, compiler
   Main-is:         Main.hs
-  build-depends:   base, directory, HTF
+  other-modules:   Tests.Compiler
+                   Tests.Property
+                   Tests.Property.Arbitrary
+                   SourceSyntax.Helpers
+                   SourceSyntax.Literal
+                   SourceSyntax.PrettyPrint
+  build-depends:   base,
+                   directory,
+                   Elm,
+                   test-framework,
+                   test-framework-hunit,
+                   test-framework-quickcheck2,
+                   HUnit,
+                   pretty,
+                   QuickCheck >= 2 && < 3,
+                   filemanip,
+                   aeson,
+                   base >=4.2 && <5,
+                   binary >= 0.6.4.0,
+                   blaze-html == 0.5.* || == 0.6.*,
+                   blaze-markup == 0.5.1.*,
+                   bytestring,
+                   cmdargs,
+                   containers >= 0.3,
+                   directory,
+                   filepath,
+                   indents,
+                   language-ecmascript >=0.15 && < 1.0,
+                   mtl >= 2,
+                   pandoc >= 1.10,
+                   parsec >= 3.1.1,
+                   pretty,
+                   text,
+                   transformers >= 0.2,
+                   union-find,
+                   unordered-containers

How to Request Features.md

@@ -0,0 +1,93 @@
+# How to make a Feature Request
+
+Adding features is hard work and has long term implications for Elm.
+If you think your particular feature is important, help make it happen
+by doing some of the background work that goes into actually adding it.
+
+### Before making a Request / Formatting:
+
+  - Make sure your feature has not already been requested. Look through the
+    email list to find similar requests.
+  - Submit feature requests by emailing the list. This allows the broadest
+    discussion and does not clutter up the GitHub repository with speculative
+    issues. I'd prefer to use the GitHub issue tracker for bug tracking and
+    issues with the existing code base.
+  - Label all feature requests with a subject like "Request: _____". For
+    example, if you want to be the umpteenth person to request type classes,
+    you would use the subject "Request: Type Classes".
+
+### Body of the Request:
+
+Your request should address all of the following issues:
+
+**General Problem:** Clearly define the purpose of adding the feature.
+What general problem do you want to solve? Why is that problem important?
+Why is it important for a functional GUI language?
+
+**Specific Use-Cases:** What are the specific cases when the general problem
+is actually an issue? How often does this case come up? Why are these cases
+important to easily designing graphical user interfaces? Why are existing
+solutions in Elm unsuitable?
+
+**Background Materials:** Are there relevant papers on the topic? Are there
+languages or libraries that already have this feature? Organize this material
+and provide a concise and helpful overview.
+
+**Alternatives:** What are all the ways to address the general problem or a
+closely related problem? For example, the semantic flexibility of type classes
+can be largely replicated with a module system in the style of ML.
+What are the strengths and weakness of each of the alternative solutions?
+
+**Suggested Approach:** Outline your specific approach. How does it address
+the general problem? How does it work? How hard is it going to be to add?
+What other language features does it depend on that need to be added first?
+Try to take a look at the relevant code to see if it would require significant
+changes. If you are suggesting an API or library changes, include an interface
+(a list of type signatures) for the functions you would like to add (perhaps
+multiple interfaces if there are many good approaches).
+
+**Known Issues:** Search for issues that people have already found. Think of
+any other possible downside and list them too. For example, one downside of
+typeclasses is that they are globally defined for each type, so you cannot
+have multiple `Ord` instances for Strings. This can lead to namespace pollution
+within a project. In general you can only implement an "interface" once per
+type, so it is very tricky to get the flexibility of ML's module functors.
+
+**Justification:** Why is the added complexity of your feature worth it? Discuss
+both implementation complexity in the compiler, and conceptual complexity that
+users must deal with. Why is your feature better than the alternative solutions?
+Why is it okay to ignore the known issues? Is there any way to overcome the known
+issues? Will it be difficult or confusing for users coming from JavaScript?
+
+### Some final notes:
+
+If for some reason you cannot provide details for some of these categories,
+explain why the category is not applicable.
+
+Re-read before posting. Is your request constructive? Is it well organized?
+Are there any details you forgot? Can anything be clarified or trimmed down?
+Considering a request takes time, so be considerate about how much work a
+reader has to do to take it seriously.
+
+A feature request is not an opportunity to be sassy or glib. Try to present
+the information and argument clearly, concisely, thoroughly, and in an unbiased
+manner.
+
+This is likely to be an iterative process. People will have comments and
+questions. Everyone please be kind. Commenters, if you think you have a
+concern, raise it as a question: "But what happens when you do blah?" instead
+of "This will break when you do blah". Assume you have misunderstood their
+proposal or only have a shallow understanding of it. Seek clarification, not victory.
+
+Comments are not a place for flame wars. Discuss specific issues. Vague
+complaining and unsupported claims should either be forgotten or developed
+into specific and well-supported concerns.
+
+I am always working hard to add cool stuff to Elm, and it is a lot of work.
+I must prioritize issues to focus on the things that have the highest impact
+for improving the quality of Elm, addressing the concerns of current users,
+and making Elm more appealing for new users. I do not have infinite time,
+so some things must receive more attention than others. I apologize in advance.
+
+And to summarize, just be cool! I want Elm to be really fun and easy to use,
+and I want your projects to be amazing!

compiler/Build/Dependencies.hs

@@ -18,7 +18,7 @@ import System.FilePath as FP
 import System.IO
 import Text.PrettyPrint (Doc)
 
-import SourceSyntax.Everything
+import qualified SourceSyntax.Module as Module
 import qualified SourceSyntax.Type as Type
 import qualified Parse.Parse as Parse
 import qualified Metadata.Prelude as Prelude
@@ -32,7 +32,7 @@ import qualified Elm.Internal.Name as N
 import qualified Elm.Internal.Version as V
 import qualified Elm.Internal.Dependencies as Deps
 
-getSortedDependencies :: [FilePath] -> Interfaces -> FilePath -> IO [String]
+getSortedDependencies :: [FilePath] -> Module.Interfaces -> FilePath -> IO [String]
 getSortedDependencies srcDirs builtIns root =
     do extras <- extraDependencies
        let allSrcDirs = srcDirs ++ Maybe.fromMaybe [] extras
@@ -86,7 +86,7 @@ sortDeps depends =
     mistakes = filter (\scc -> length scc > 1) sccs
     msg = "A cyclical module dependency or was detected in:\n"
 
-readDeps :: [FilePath] -> Interfaces -> FilePath -> ErrorT String IO [Deps]
+readDeps :: [FilePath] -> Module.Interfaces -> FilePath -> ErrorT String IO [Deps]
 readDeps srcDirs builtIns root = do
   let ifaces = (Set.fromList . Map.keys) builtIns
   State.evalStateT (go ifaces root) Set.empty

compiler/Build/Source.hs

@@ -11,7 +11,9 @@ import System.Exit
 import System.FilePath as FP
 import Text.PrettyPrint (Doc)
 
-import SourceSyntax.Everything
+import SourceSyntax.Declaration
+import SourceSyntax.Module
+import qualified SourceSyntax.Expression as Expr
 import qualified SourceSyntax.Type as Type
 import qualified Parse.Parse as Parse
 import qualified Metadata.Prelude as Prelude
@@ -38,7 +40,7 @@ build noPrelude interfaces source =
      let exports'
              | null exs =
                  let get = Set.toList . SD.boundVars in
-                 concat [ get pattern | Definition (Def pattern _) <- decls ] ++
+                 concat [ get pattern | Definition (Expr.Def pattern _) <- decls ] ++
                  concat [ map fst ctors | Datatype _ _ ctors <- decls ] ++
                  [ name | TypeAlias name _ (Type.Record _ _) <- decls ]
              | otherwise = exs
@@ -49,7 +51,7 @@ build noPrelude interfaces source =
            exports = exports',
            imports = ims,
            -- reorder AST into strongly connected components
-           program = SD.sortDefs . dummyLet $ TcDecl.toExpr decls,
+           program = SD.sortDefs . Expr.dummyLet $ TcDecl.toExpr decls,
            types = Map.empty,
            datatypes = [ (name,vars,ctors) | Datatype name vars ctors <- decls ],
            fixities = [ (assoc,level,op) | Fixity assoc level op <- decls ],

compiler/Elm/Internal/Dependencies.hs

@@ -10,6 +10,7 @@ import qualified Data.ByteString.Lazy as BS
 import qualified Data.HashMap.Strict as Map
 import qualified Elm.Internal.Name as N
 import qualified Elm.Internal.Version as V
+import qualified Elm.Internal.Paths as Path
 
 data Deps = Deps
     { name :: N.Name
@@ -47,10 +48,6 @@ instance FromJSON Deps where
                      Right nm -> return nm
 
            exposed <- get obj "exposed-modules" "a list of modules exposed to users"
-           when (null exposed) $
-                fail "there are no 'exposed-modules'.\n\
-                     \At least one module must be exposed \
-                     \for anyone to use this library!"
 
            elmVersion <- get obj "elm-version" "the version of the Elm compiler you are using"
 
@@ -76,7 +73,8 @@ get obj field desc =
        case maybe of
          Just value -> return value
          Nothing -> fail $ "Missing field " ++ show field ++ ", " ++ desc ++ ".\n" ++
-                           "    <https://github.com/evancz/rainbow-palette/blob/master/elm_dependencies.json>"
+                           "    Check out an example " ++ Path.dependencyFile ++ " file here:" ++
+                           "    <https://github.com/evancz/automaton/blob/master/elm_dependencies.json>"
 
 repoToName :: String -> Either String N.Name
 repoToName repo

compiler/Elm/Internal/Version.hs

@@ -13,7 +13,7 @@ import qualified Data.Version as Version
 
 elmVersion :: Version
 elmVersion = V ns ""
-    where (Version.Version ns _) =This.version
+    where (Version.Version ns _) = This.version
 
 -- Data representation