07712e9 · elk · git.iko.soy

git.iko.soy/elk

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Work on TODO for bad type variables in type aliases

07712e9Evan Czaplicki9 years ago

src/Canonicalize/Environment/Local.hs+2−3

compare with master

unifiedsplit

@@ -219,12 +219,11 @@ checkAliasFreeVars (Valid.Alias aliasRegion (A.At _ name) args tipe) =

219 if Map.size boundVars == overlap && Map.size freeVars == overlap

220 then Result.ok (map A.toValue args)

221 else

222− let toLoc (arg, region) = A.At region arg in

223 Result.throw $

222 Result.throw $

224 Error.TypeVarsMessedUpInAlias aliasRegion name

223 Error.TypeVarsMessedUpInAlias aliasRegion name

225 (map A.toValue args)

224 (map A.toValue args)

226− (map toLoc (Map.toList (Map.difference boundVars freeVars)))

225+ (Map.toList (Map.difference boundVars freeVars))

227− (map toLoc (Map.toList (Map.difference freeVars boundVars)))

226+ (Map.toList (Map.difference freeVars boundVars))

228

227

229

228

230addFreeVars :: Map.Map N.Name R.Region -> Src.Type -> Map.Map N.Name R.Region

229addFreeVars :: Map.Map N.Name R.Region -> Src.Type -> Map.Map N.Name R.Region

src/Reporting/Error/Canonicalize.hs+122−104

@@ -73,7 +73,7 @@ data Error

73 | Shadowing N.Name R.Region R.Region

74 | TupleLargerThanThree R.Region

75 | TypeVarsUnboundInUnion R.Region N.Name [N.Name] (N.Name, R.Region) [(N.Name, R.Region)]

76− | TypeVarsMessedUpInAlias R.Region N.Name [N.Name] [A.Located N.Name] [A.Located N.Name]

76+ | TypeVarsMessedUpInAlias R.Region N.Name [N.Name] [(N.Name, R.Region)] [(N.Name, R.Region)]

79data BadArityContext

@@ -735,114 +735,133 @@ toReport source err =

735 ]

736 )

737

738− TypeVarsUnboundInUnion unionRegion tipe allVars (unboundVar, varRegion) unboundVars ->

738+ TypeVarsUnboundInUnion unionRegion typeName allVars unbound unbounds ->

739− let

739+ unboundTypeVars source unionRegion ["type"] typeName allVars unbound unbounds

740− backQuote name =

741− "`" <> H.nameToDoc name <> "`"

742

740

741+ TypeVarsMessedUpInAlias aliasRegion typeName allVars unusedVars unboundVars ->

742+ case (unusedVars, unboundVars) of

743+ (unused:unuseds, []) ->

744+ let

745+ backQuote name =

746+ "`" <> H.nameToDoc name <> "`"

747+

748+ allUnusedNames =

749+ map fst unusedVars

750+

743− (title, subRegion, overview) =

751+ (title, subRegion, overview, stuff) =

744− case map fst unboundVars of

752+ case unuseds of

745− [] ->

753+ [] ->

746− ( "UNBOUND TYPE VARIABLE"

754+ ("UNUSED TYPE VARIABLE"

747− , Just varRegion

755+ , Just (snd unused)

748− , ["The",backQuote tipe,"type","uses","an","unbound","type","variable"

756+ , ["Type","alias",backQuote typeName,"does","not","use","the"

757+ ,backQuote (fst unused),"type","variable."

758+ ]

749− ,H.dullyellow (backQuote unboundVar),"in","its","definition:"

759+ , [H.dullyellow (backQuote (fst unused))]

760+ )

761+

762+ _:_ ->

763+ ( "UNUSED TYPE VARIABLES"

764+ , Nothing

765+ , ["Type","variables"]

766+ ++ H.commaSep "and" id (map H.nameToDoc allUnusedNames)

767+ ++ ["are","unused","in","the",backQuote typeName,"definition."]

768+ , H.commaSep "and" H.dullyellow (map H.nameToDoc allUnusedNames)

769+ )

770+ in

771+ Report.Report title aliasRegion [] $

772+ Report.toCodeSnippet source aliasRegion subRegion

773+ (

774+ H.fillSep overview

775+ ,

776+ H.stack

777+ [ H.fillSep $

778+ ["I","recommend","removing"] ++ stuff ++ ["from","the","declaration,","like","this:"]

779+ , H.indent 4 $ H.hsep $

780+ ["type","alias",H.nameToDoc typeName]

781+ ++ map H.nameToDoc (filter (\v -> notElem v allUnusedNames) allVars)

782+ ++ ["=", "..."]

783+ , H.reflow $

784+ "Why? Well, if I allowed `type alias Height a = Float` I would need to answer\

785+ \ some weird questions. Is `Height Bool` the same as `Float`? Is `Height Bool`\

786+ \ the same as `Height Int`? My solution is to not need to ask them!"

750− ]

787+ ]

751 )

788 )

752

789

753− vars ->

790+ ([], unbound:unbounds) ->

754− ( "UNBOUND TYPE VARIABLES"

791+ unboundTypeVars source aliasRegion ["type","alias"] typeName allVars unbound unbounds

755− , Nothing

792+

756− , ["Type","variables"]

793+ (_, _) ->

757− ++ H.commaSep "and" H.dullyellow (H.nameToDoc unboundVar : map H.nameToDoc vars)

794+ error "TODO TypeVarsMessedUpInAlias"

758− ++ ["are","unbound","in","the",backQuote tipe,"type","definition:"]

795+ {-

796+ Report.Report "TYPE VARIABLE PROBLEMS" aliasRegion [] $

797+ Report.toCodeSnippet source region Nothing

798+ (

799+ H.reflow $

800+ "Type alias `" <> typeName <> "` has some type variable problems."

801+ ,

802+ H.stack

803+ [ H.reflow $

804+ "The definition uses certain type variables ("

805+ <> H.commaSep unused <> ") but they do not appear in the aliased type. "

806+ <> "Furthermore, the aliased type says it uses type variables ("

807+ <> H.commaSep unbound

808+ <> ") that do not appear in the declaration."

809+ , text "You probably need to change the declaration like this:"

810+ , H.dullyellow $ hsep $

811+ map text ("type" : "alias" : typeName : filter (`notElem` unused) givenVars ++ unbound ++ ["=", "..."])

812+ ]

759 )

813 )

760− in

814+ -}

761− Report.Report title unionRegion [] $

815+

762− Report.toCodeSnippet source unionRegion subRegion

816+

763− (

817+

818+-- BAD TYPE VARIABLES

819+

820+

821+unboundTypeVars :: Code.Source -> R.Region -> [H.Doc] -> N.Name -> [N.Name] -> (N.Name, R.Region) -> [(N.Name, R.Region)] -> Report.Report

822+unboundTypeVars source declRegion tipe typeName allVars (unboundVar, varRegion) unboundVars =

823+ let

824+ backQuote name =

825+ "`" <> H.nameToDoc name <> "`"

826+

764− H.fillSep overview

827+ (title, subRegion, overview) =

765− ,

766− H.stack

767− [ H.reflow $

768− "You probably need to change the type declaration to something like this:"

769− , H.indent 4 $ H.hsep $

770− ["type", H.nameToDoc tipe]

771− ++ map H.nameToDoc allVars

772− ++ map (H.green . H.nameToDoc) (unboundVar : map fst unboundVars)

828+ case map fst unboundVars of

773− ++ ["=", "..."]

829+ [] ->

774− , H.reflow $

830+ ( "UNBOUND TYPE VARIABLE"

775− "Why? Well, imagine one `" ++ N.toString tipe ++ "` where `" ++ N.toString unboundVar ++

831+ , Just varRegion

776− "` is an Int and another where it is a Bool. When we explicitly list the type\

832+ , ["The",backQuote typeName]

777− \ variables, the type checker can see that they are actually different types."

833+ ++ tipe

778− ]

834+ ++ ["uses","an","unbound","type","variable",H.dullyellow (backQuote unboundVar),"in","its","definition:"]

779 )

835 )

780

836

781− TypeVarsMessedUpInAlias _ _ _ _ _ ->

837+ vars ->

782− error "TODO TypeVarsMessedUpInAlias"

783−

784−

785−

786−-- UnboundTypeVarsInUnion typeName givenVars unbound ->

787−-- unboundTypeVars "type" typeName givenVars unbound

788−

789−-- UnboundTypeVarsInAlias typeName givenVars unbound ->

790−-- unboundTypeVars "type alias" typeName givenVars unbound

791−

792−-- UnusedTypeVarsInAlias typeName givenVars unused ->

793−-- Report.report

794−-- "UNUSED TYPE VARIABLES"

795−-- Nothing

796−-- ( "Type alias `" <> typeName <> "` cannot have unused type variables: "

797−-- <> H.commaSep unused

798−-- )

799−-- ( H.stack

800−-- [ text "You probably need to change the declaration like this:"

801−-- , H.dullyellow $ hsep $

802−-- map text ("type" : "alias" : typeName : filter (`notElem` unused) givenVars ++ ["=", "..."])

803−-- ]

804−-- )

805−

806−-- MessyTypeVarsInAlias typeName givenVars unused unbound ->

807−-- Report.report

808−-- "TYPE VARIABLE PROBLEMS"

809−-- Nothing

810−-- ( "Type alias `" <> typeName <> "` has some problems with type variables."

811−-- )

812−-- ( H.stack

813−-- [ H.reflow $

814−-- "The declaration says it uses certain type variables ("

815−-- <> H.commaSep unused <> ") but they do not appear in the aliased type. "

816−-- <> "Furthermore, the aliased type says it uses type variables ("

817−-- <> H.commaSep unbound

818−-- <> ") that do not appear in the declaration."

819−-- , text "You probably need to change the declaration like this:"

820−-- , H.dullyellow $ hsep $

821−-- map text ("type" : "alias" : typeName : filter (`notElem` unused) givenVars ++ unbound ++ ["=", "..."])

822−-- ]

823−-- )

824−

825−

826−--unboundTypeVars :: Text -> Text -> [Text] -> [Text] -> Report.Report

827−--unboundTypeVars declKind typeName givenVars unboundVars =

828−-- Report.report

829−-- "UNBOUND TYPE VARIABLES"

838+ ( "UNBOUND TYPE VARIABLES"

830−-- Nothing

839+ , Nothing

831−-- ( H.capitalize declKind <> " `" <> typeName <> "` must declare its use of type variable"

840+ , ["Type","variables"]

832−-- <> H.commaSep unboundVars

841+ ++ H.commaSep "and" H.dullyellow (H.nameToDoc unboundVar : map H.nameToDoc vars)

833−-- )

842+ ++ ["are","unbound","in","the",backQuote typeName] ++ tipe ++ ["definition:"]

843+ )

844+ in

845+ Report.Report title declRegion [] $

846+ Report.toCodeSnippet source declRegion subRegion

847+ (

848+ H.fillSep overview

849+ ,

834−-- ( H.stack

850+ H.stack

851+ [ H.reflow $

835−-- [ text "You probably need to change the declaration like this:"

852+ "You probably need to change the declaration to something like this:"

836−-- , hsep $

853+ , H.indent 4 $ H.hsep $

837−-- map text (declKind : typeName : givenVars)

854+ tipe

855+ ++ [H.nameToDoc typeName]

856+ ++ map H.nameToDoc allVars

838−-- ++ map (H.dullyellow . text) unboundVars

857+ ++ map (H.green . H.nameToDoc) (unboundVar : map fst unboundVars)

839−-- ++ map text ["=", "..."]

858+ ++ ["=", "..."]

840−-- , reflow $

859+ , H.reflow $

841−-- "Here's why. Imagine one `" <> typeName <> "` where `" <> head unboundVars <>

860+ "Why? Well, imagine one `" ++ N.toString typeName ++ "` where `" ++ N.toString unboundVar ++

842−-- "` is an Int and another where it is a Bool. When we explicitly list the type\

861+ "` is an Int and another where it is a Bool. When we explicitly list the type\

843−-- \ variables, the type checker can see that they are actually different types."

862+ \ variables, the type checker can see that they are actually different types."

844−-- ]

863+ ]

845−-- )

864+ )

846

865

847

866

848

867

@@ -921,7 +940,6 @@ ambiguousName source region maybePrefix name possibleHomes thing =

921

940

922

941

923

942

924−

925-- NOT FOUND

943-- NOT FOUND

926

944

927

945