b768c73..master · typeable/xml-isogen

git.iko.soy/typeable/xml-isogen

17 files changed+504−89

unifiedsplit

.gitignore+5 CHANGELOG.md+5 README.md+284−1 ghc-802.yaml+4 ghc-822.yaml+4 ghc-844.yaml+4 shell.nix+17 src/Data/THGen/Orphans.hs+11 src/Data/THGen/XML.hs+7−8 src/Data/THGen/XML/Internal.hs+76−72 src/Text/XML/Nillable.hs+41 stack-10.0.yaml+8 stack-18.18.yaml+9 stack-19.6.yaml+9 stack.yaml+8−3 test/TestDefs.hs+4−4 xml-isogen.cabal+8−1

.gitignore+5

@@ -3,3 +3,8 @@ dist

33.stack-work

44.cabal-sandbox/

55cabal.sandbox.config

6+dist-newstyle/

7+default.nix

8+# vim backup and swap files

9+*~

10+.*.swp

CHANGELOG.md+5

@@ -1,6 +1,11 @@

11HEAD

22------

4+* Add lenient parsers support (#29)

5+* Rename Both to ParserAndGenerator (#27)

6+* Add Nillable newtype (#24)

7+* Include digits in the auto-gerenated prefix (#22)

490.3.0

510------

611

README.md+284−1

@@ -6,4 +6,287 @@ TemplateHaskell generators for XML-isomorphic data types, including

66instances for parsing and rendering. A convenient DSL to define those

77types.

9−This is similar to XSD but is Haskell-specific.

9+Essentially it's a haskell DSL which allows its users to generate XML parsers and generators for haskell datatypes.

10+See also [xsd-isogen](https://github.com/typeable/xsd-isogen)

11+

12+## Tutorial

13+

14+Lets go through series of examples. First things first:

15+

16+```haskell

17+{-# LANGUAGE TemplateHaskell #-}

18+{-# LANGUAGE OverloadedStrings #-}

19+{-# LANGUAGE DeriveGeneric #-}

20+

21+module Tutorial

22+where

23+

24+import Prelude hiding ((^))

25+import Control.DeepSeq -- from deepseq

26+import Data.Text

27+import Data.THGen.XML -- from xml-isogen

28+import Text.XML.Writer -- from xml-conduit-writer

29+import Text.XML.DOM.Parser -- from dom-parser

30+```

31+

32+### Records

33+

34+Lets say we want to parse and/or generate an XML file of the following form:

35+

36+```XML

37+<?xml version="1.0" encoding="UTF-8"?>

38+<person>

39+ <name>

40+ John

41+ </name>

42+ <email>

43+ john@example.com

44+ </email>

45+</person>

46+```

47+

48+Person has a name and an email, and email could be omitted. With `xml-isogen` it's

49+enough to write the following definition:

50+

51+```haskell

52+"Person" =:= record ParserAndGenerator

53+ ! "name" [t|Text|]

54+ ? "email" [t|Text|]

55+```

56+

57+At this point you can load the module into `ghci` and check what was generated for us

58+so far:

59+

60+```

61+*Tutorial> :browse

62+data XmlPerson

63+ = XmlPerson {_xpName :: !Text, _xpEmail :: !(Maybe Text)}

64+xpEmail ::

65+ lens-4.18.1:Control.Lens.Type.Lens' XmlPerson (Maybe Text)

66+xpName :: lens-4.18.1:Control.Lens.Type.Lens' XmlPerson Text

67+```

68+

69+We have a data type `XmlPerson` with two fields and two lenses. Note that the

70+fields have a prefix built of an underscore and all upper case characters

71+and digits of the type name.

72+

73+

74+Lets take a closer look at `XmlPerson`:

75+

76+```

77+*Tutorial> :i XmlPerson

78+data XmlPerson

79+ = XmlPerson {_xpName :: !Text, _xpEmail :: !(Maybe Text)}

80+ -- Defined at Tutorial.hs:13:1

81+instance Show XmlPerson -- Defined at Tutorial.hs:13:1

82+instance Eq XmlPerson -- Defined at Tutorial.hs:13:1

83+instance FromDom XmlPerson -- Defined at Tutorial.hs:13:1

84+instance ToXML XmlPerson -- Defined at Tutorial.hs:13:1

85+

86+```

87+

88+We have

89+[FromDom](https://hackage.haskell.org/package/dom-parser-3.1.0/docs/Text-XML-DOM-Parser-FromDom.html#t:FromDom)

90+and

91+[ToXML](https://hackage.haskell.org/package/xml-conduit-writer-0.1.1.2/docs/Text-XML-Writer.html#t:ToXML)

92+instance generated for us. That's because

93+we instructed `xml-isogen` to generate them using the `ParserAndGenerator` noun. You can specify

94+also `Parser` or `Generator` if you want only one of them.

95+

96+The `_xpEmail` field is optional; that's because we prefixed it with `?` modifier.

97+Here is the list of possible modifiers that affect types:

98+

99+Modifier | Description | Generated Type

100+--- | --- | ---

101+`!` | required | `a`

102+`?` | optional | `Maybe a`

103+`*` | repeated | `[a]`

104+`+` | nonempty | `NonEmpty a`

105+

106+### Supported types

107+

108+Fields in a record may have any types as long as they are instances of `Eq`, `Show`,

109+`NFData`, `FromDom` (for the parser) and `ToXml` (for the generator). Remember

110+though that TemplateHaskell requires types to be available before they are used

111+in a splice.

112+

113+You can omit field types altogether, in that case the type will be assumed to be a

114+capitalized field name with an `Xml` prefix.

115+It's your responsibility to make sure that type exists.

116+Example:

117+

118+```haskell

119+newtype XmlEmail = XmlEmail Text

120+ deriving (Eq, Show, NFData, ToXML)

121+

122+instance FromDom XmlEmail where

123+ fromDom = XmlEmail <$> fromDom

124+

125+"Example1" =:= record Parser

126+ ! "email" -- will have type XmlEmail

127+```

128+

129+### Enumerations

130+

131+Often XML element can contain only limited number of possible values. Lets define

132+a type `Status` that can have only values `Active`, `Pending` or `Deleted`:

133+

134+```haskell

135+"Status" =:= enum ParserAndGenerator

136+ & "Active"

137+ & "Pending"

138+ & "Deleted"

139+```

140+

141+This definition will generate the following type for us:

142+

143+```haskell

144+data XmlStatus

145+ = XmlStatusActive

146+ | XmlStatusPending

147+ | XmlStatusDeleted

148+ | UnknownXmlStatus !String

149+```

150+

151+It has all the necessary instances, so you can use it as a type for a field.

152+

153+### Append content

154+

155+Sometimes the XML you are dealing with contains a mix of elements and immediate

156+content. Something like the following:

157+

158+```XML

159+<?xml version="1.0" encoding="UTF-8"?>

160+<example>

161+ <field1>

162+ I am

163+ </field1>

164+ totally

165+ <field2>

166+ weird

167+ </field2>

168+</example>

169+```

170+

171+You can model this with an "append content" modifier `^`. It will instruct

172+`xml-isogen` to append content of the field as it is, without wrapping it

173+into an XML element. For our case it may look like this:

174+

175+```haskell

176+"Example2" =:= record ParserAndGenerator

177+ ! "field1" [t|Text|]

178+ ^ "mixed" [t|Text|]

179+ ! "field2" [t|Text|]

180+```

181+

182+After parsing the XML above, we'll get the following:

183+

184+```haskell

185+XmlExample2 {_xe2Field1 = "I am", _xe2Mixed = "totally", _xe2Field2 = "weird"}

186+```

187+

188+### Attributes

189+

190+`xml-isogen` also supports XML attributes using `!%` and `?%` modifiers:

191+

192+```haskell

193+"Example3" =:= record ParserAndGenerator

194+ ! "field1" [t|Text|]

195+ !% "attribute1" [t|Text|]

196+ ?% "attribute2" [t|Text|]

197+

198+"Body" =:= record ParserAndGenerator

199+ ! "root" [t|XmlExample3|]

200+```

201+

202+The following two types will be generated:

203+

204+```haskell

205+data XmlExample3

206+ = XmlExample3 {_xe3Field1 :: !Text,

207+ _xe3Attribute1 :: !Text,

208+ _xe3Attribute2 :: !(Maybe Text)}

209+

210+newtype XmlBody = XmlBody {_xbRoot :: XmlExample3}

211+```

212+

213+The `_xe3Attribute2` is optional because we used `?%` modifier. Attributes will be

214+attached to parent XML element. Here is an example of the generated XML file:

215+

216+```XML

217+<root attribute1="world">

218+ <field1>

219+ hello

220+ </field1>

221+</root>

222+```

223+

224+Note that attributes are attached to the parent XML element, that's why we needed

225+`XmlBody` type here.

226+

227+And here is what you get after parsing the XML:

228+

229+```haskell

230+XmlExample3 {_xe3Field1 = "hello", _xe3Attribute1 = "world", _xe3Attribute2 = Nothing}

231+```

232+

233+### Namespaces

234+

235+Often XSD schema requires XML elements to be qualified with a namespace. To instruct

236+`xml-isogen` to qualify fields, specify namespace is a curly brackets:

237+

238+```haskell

239+"Example4" =:= record ParserAndGenerator

240+ ! "field1" [t|Text|]

241+ ! "{http://example.com/1}field2" [t|Text|]

242+ ! "{http://example.com/2}field3" [t|Text|]

243+```

244+

245+Here is the generated XML:

246+

247+```XML

248+<field1>

249+ hello

250+</field1>

251+<field2 xmlns="http://example.com/1">

252+ world

253+</field2>

254+<field3 xmlns="http://example.com/2">

255+ !

256+</field3>

257+```

258+

259+### Nillable types

260+

261+Sometimes optional element in XML are encoded using `nil="true"` attribute instead of

262+omitting the element. (The `nil` attribute comes from `http://www.w3.org/2001/XMLSchema-instance` namespace). With `xml-isogen` you handle it using the `Nillable` type:

263+

264+```haskell

265+"Example5" =:= record ParserAndGenerator

266+ ! "field" [t|Nillable Text|]

267+```

268+

269+If the field contains the value `Nothing`, like this

270+

271+```haskell

272+XmlExample5 { _xe5Field = Nillable Nothing}

273+```

274+

275+then the following XML will be generated:

276+

277+```XML

278+<field

279+ xmlns:ns="http://www.w3.org/2001/XMLSchema-instance"

280+ ns:nil="true"

281+/>

282+```

283+

284+## Development

285+

286+To start working with `xml-isogen` using nix use:

287+

288+```

289+nix-shell --packages cabal2nix --run "cabal2nix ." > default.nix

290+nix-shell

291+cabal v2-build

292+```

ghc-802.yaml+4

@@ -1,3 +1,7 @@

1+nix:

2+ packages:

3+ - zlib

15resolver: lts-9.21

37packages:

ghc-822.yaml+4

@@ -1 +1,5 @@

1+nix:

2+ packages:

3+ - zlib

15resolver: lts-11.22

ghc-844.yaml+4

@@ -1,3 +1,7 @@

1+nix:

2+ packages:

3+ - zlib

15resolver: lts-12.16

26extra-deps:

37- dom-parser-3.1.0

shell.nixnew file+17

@@ -0,0 +1,17 @@

1+{ nixpkgs ? import <nixpkgs> {}, compiler ? "default" }:

3+let

5+ inherit (nixpkgs) pkgs;

7+ f = import ./default.nix;

9+ haskellPackages = if compiler == "default"

10+ then pkgs.haskellPackages

11+ else pkgs.haskell.packages.${compiler};

12+

13+ drv = haskellPackages.callPackage f {};

14+

15+in

16+

17+ if pkgs.lib.inNixShell then drv.env else drv

src/Data/THGen/Orphans.hsnew file+11

@@ -0,0 +1,11 @@

1+{-# OPTIONS_GHC -fno-warn-orphans #-}

3+module Data.THGen.Orphans

4+where

6+import Data.Scientific

7+import qualified Data.Text as Text

8+import Text.XML.Writer

10+instance ToXML Scientific where

11+ toXML = content . Text.pack . formatScientific Fixed Nothing

src/Data/THGen/XML.hs+7−8

@@ -22,7 +22,7 @@ wrapper around the field type:

2222

2323Example 1.

2424

25−> "Color" =:= enum Both

25+> "Color" =:= enum ParserAndGenerator

2626> & "R"

2727> & "G"

2828> & "B"

@@ -40,7 +40,7 @@ to be either @R@, @G@ or @B@.

4040

4141Example 2.

4242

43−> "Message" =:= record Both Lens

43+> "Message" =:= record ParserAndGenerator

4444> ! "author"

4545> + "recipient"

4646> ? "message" [t|Text|]

@@ -78,12 +78,9 @@ the data type to be generated. The prefix for the record fields is

7878inferred automatically by taking all of the uppercase letters in the

7979name. You can override it manually like so:

8080

81−> "Reference" "ref" =:= record Parser Lens

81+> "Reference" "ref" =:= record Parser

8282> ...

8383

84−Second argument to @record@ either enabled lens generation for records fields

85−or disables it for use with DuplicateRecordFields and, possibly, generic-lens.

86−

8784To describe a record field you must supply its name as it appears

8885in the XML tag, prefixed by its repetition kind:

8986

@@ -96,7 +93,7 @@ The type of the field is inferred automatically from its name, so

9693if the field is called @"author"@ its type will be @Author@. You can

9794override the type by specifying it in quasiquotes like so:

9895

99−> "Message" =:= record Both NoLens

96+> "Message" =:= record ParserAndGenerator

10097> ! "author" [t|Person|].

10198> ...

10299

@@ -112,7 +109,6 @@ module Data.THGen.XML

112109 , PrefixName(..)

113110 , ExhaustivenessName(..)

114111 , GenType(..)

115− , GenerateLens(..)

116112 , record

117113 , enum

118114 , (!)

@@ -128,9 +124,12 @@ module Data.THGen.XML

128124 , Text

129125 , P.Int

130126 , P.Integer

127+ , Nillable(..)

131128 ) where

132129

133130import Data.THGen.Enum

131+import Data.THGen.Orphans ()

134132import Data.THGen.XML.Internal

135133import Data.Text

134+import Text.XML.Nillable

136135import qualified Prelude as P

src/Data/THGen/XML/Internal.hs+76−72

@@ -5,7 +5,7 @@

55module Data.THGen.XML.Internal where

77import Control.DeepSeq

8−import Control.Lens hiding (repeated, enum, (&))

8+import Control.Lens hiding (repeated, enum, (&), Strict)

99import Control.Lens.Internal.FieldTH (makeFieldOpticsForDec)

1010import qualified Data.Char as C

1111import Data.List.NonEmpty (NonEmpty)

@@ -15,7 +15,7 @@ import Data.THGen.Compat as THC

1515import Data.THGen.Enum

1616import qualified Data.Text as T

1717import GHC.Generics (Generic)

18−import Language.Haskell.TH as TH

18+import Language.Haskell.TH as TH hiding (Strict)

1919import Prelude hiding ((+), (*), (^))

2020import qualified Text.XML as X

2121import Text.XML.DOM.Parser hiding (parseContent)

@@ -23,26 +23,22 @@ import Text.XML.DOM.Parser.Internal.Content

2323import Text.XML.ParentAttributes

2424import qualified Text.XML.Writer as XW

2525

26+data ParserMode

27+ = Strict

28+ | Lenient

2629

27−-- | Marks the type of code generation:

28−-- Parser - generate only instances for xml parsing (@FromDom@)

29−-- Generator - generate only @ToXML@ instances

30−-- Both - generate @FromDom@ and @ToXML@ instances

31−data GenType = Parser | Generator | Both

30+data GenType

31+ = Parser

32+ | Generator

33+ | ParserAndGenerator

34+ | LenientParser

35+ | LenientParserAndGenerator

3236

33−{- | Marks the style of code generation regarding records fields

34−@LensRenaming@ - fields get renamed by prefixing the field name with

35−'_' and lowercased capital letter used in the type name.

36−e.g. for

37−

38−> "MyNewDataType" =:= record genType LensRenaming

39−> * "field1"

40−

41−field will be renamed to `_mndtField1` and lens `mndtField1` will be created.

42−

43−@NoLens@ - no field renaming and no lens generation.

44−-}

45−data GenerateLens = LensRenaming | NoLens

37+isLenientType :: GenType -> Bool

38+isLenientType = \case

39+ LenientParser -> True

40+ LenientParserAndGenerator -> True

41+ _ -> False

4642

4743data XmlFieldPlural

4844 = XmlFieldPluralMandatory -- Occurs exactly 1 time (Identity)

@@ -73,7 +69,7 @@ data IsoXmlDescRecordPart

7369 | IsoXmlDescRecordAttribute IsoXmlDescAttribute

7470 | IsoXmlDescRecordContent IsoXmlDescContent

7571

76−data IsoXmlDescRecord = IsoXmlDescRecord GenType GenerateLens [IsoXmlDescRecordPart]

72+data IsoXmlDescRecord = IsoXmlDescRecord GenType [IsoXmlDescRecordPart]

7773

7874makePrisms ''IsoXmlDescRecord

7975

@@ -94,34 +90,26 @@ appendField

9490 -> IsoXmlDescRecord

9591 -> IsoXmlDescPreField

9692 -> IsoXmlDescRecord

97−appendField

98− plural

99− (IsoXmlDescRecord genType generateLens fields)

100− (IsoXmlDescPreField name ty) =

101− let xfield = IsoXmlDescRecordField $ IsoXmlDescField plural name ty

102− in IsoXmlDescRecord genType generateLens (xfield:fields)

93+appendField plural (IsoXmlDescRecord genType fields) (IsoXmlDescPreField name ty) =

94+ let xfield = IsoXmlDescRecordField $ IsoXmlDescField plural name ty

95+ in IsoXmlDescRecord genType (xfield:fields)

10396

10497appendAttribute

10598 :: XmlAttributePlural

10699 -> IsoXmlDescRecord

107100 -> IsoXmlDescPreAttribute

108101 -> IsoXmlDescRecord

109−appendAttribute

110− plural

111− (IsoXmlDescRecord genType generateLens fields)

112− (IsoXmlDescPreAttribute name ty) =

113− let xattribute = IsoXmlDescRecordAttribute $ IsoXmlDescAttribute plural name ty

114− in IsoXmlDescRecord genType generateLens (xattribute:fields)

102+appendAttribute plural (IsoXmlDescRecord genType fields) (IsoXmlDescPreAttribute name ty) =

103+ let xattribute = IsoXmlDescRecordAttribute $ IsoXmlDescAttribute plural name ty

104+ in IsoXmlDescRecord genType (xattribute:fields)

115105

116106appendContent

117107 :: IsoXmlDescRecord

118108 -> IsoXmlDescPreContent

119109 -> IsoXmlDescRecord

120−appendContent

121− (IsoXmlDescRecord genType generateLens fields)

122− (IsoXmlDescPreContent name ty) =

123− let xcontent = IsoXmlDescRecordContent $ IsoXmlDescContent name ty

124− in IsoXmlDescRecord genType generateLens (xcontent:fields)

110+appendContent (IsoXmlDescRecord genType fields) (IsoXmlDescPreContent name ty) =

111+ let xcontent = IsoXmlDescRecordContent $ IsoXmlDescContent name ty

112+ in IsoXmlDescRecord genType (xcontent:fields)

125113

126114(!), (?), (*), (+) :: IsoXmlDescRecord -> IsoXmlDescPreField -> IsoXmlDescRecord

127115(!) = appendField XmlFieldPluralMandatory

@@ -159,11 +147,11 @@ class Description name desc | desc -> name where

159147infix 0 =:=

160148

161149instance Description PrefixName IsoXmlDescRecord where

162− prefixName =:= (IsoXmlDescRecord genType generateLens descRecordParts) =

163− isoXmlGenerateDatatype genType generateLens prefixName (reverse descRecordParts)

150+ prefixName =:= (IsoXmlDescRecord genType descRecordParts) =

151+ isoXmlGenerateDatatype genType prefixName (reverse descRecordParts)

164152

165−record :: GenType -> GenerateLens -> IsoXmlDescRecord

166−record gt gl = IsoXmlDescRecord gt gl []

153+record :: GenType -> IsoXmlDescRecord

154+record gt = IsoXmlDescRecord gt []

167155

168156enum :: GenType -> IsoXmlDescEnum

169157enum gt = IsoXmlDescEnum gt []

@@ -172,7 +160,7 @@ instance Description ExhaustivenessName IsoXmlDescEnum where

172160 exhaustivenessName =:= (IsoXmlDescEnum genType descEnumCons) =

173161 isoXmlGenerateEnum genType exhaustivenessName (reverse descEnumCons)

174162

175−instance IsString (TH.TypeQ -> IsoXmlDescPreField) where

163+instance (m ~ Q) => IsString (m TH.Type -> IsoXmlDescPreField) where

176164 fromString = IsoXmlDescPreField

177165

178166instance IsString IsoXmlDescPreField where

@@ -180,10 +168,10 @@ instance IsString IsoXmlDescPreField where

180168 where

181169 ty = (TH.conT . TH.mkName) ("Xml" ++ over _head C.toUpper (xmlLocalName name))

182170

183−instance IsString (TH.TypeQ -> IsoXmlDescPreAttribute) where

171+instance (m ~ Q) => IsString (m TH.Type -> IsoXmlDescPreAttribute) where

184172 fromString = IsoXmlDescPreAttribute

185173

186−instance IsString (TH.TypeQ -> IsoXmlDescPreContent) where

174+instance (m ~ Q) => IsString (m Type -> IsoXmlDescPreContent) where

187175 fromString = IsoXmlDescPreContent

188176

189177instance IsString IsoXmlDescPreAttribute where

@@ -209,7 +197,7 @@ instance IsString ExhaustivenessName where

209197 fromString strName = ExhaustivenessName strName NonExhaustive

210198

211199makeNamePrefix :: String -> String

212−makeNamePrefix = map C.toLower . filter C.isUpper

200+makeNamePrefix = map C.toLower . filter (\c -> C.isUpper c || C.isDigit c)

213201

214202funSimple :: TH.Name -> TH.ExpQ -> TH.DecQ

215203funSimple name body = TH.funD name [ TH.clause [] (TH.normalB body) [] ]

@@ -237,11 +225,14 @@ isoXmlGenerateEnum genType (ExhaustivenessName strName' exh) enumCons = do

237225 (return [])

238226 [t|ToXmlAttribute $(TH.conT name)|]

239227 [funSimple 'toXmlAttribute [e|T.pack . show|]]

240− genFromDomInst = do

228+ genFromDomInst mode = do

241229 TH.instanceD

242230 (return [])

243231 [t|FromDom $(TH.conT name)|]

244− [funSimple 'fromDom [e|parseContent readContent|]]

232+ [case mode of

233+ Strict -> funSimple 'fromDom [e|parseContent readContent|]

234+ Lenient -> funSimple 'fromDom [e|ignoreBlank $ parseContent readContent|]

235+ ]

245236 genFromAttributeInst = do

246237 TH.instanceD

247238 (return [])

@@ -253,36 +244,36 @@ isoXmlGenerateEnum genType (ExhaustivenessName strName' exh) enumCons = do

253244 toXmlAttributeInst <- genToXmlAttributeInst

254245 return $ enumDecls ++ [toXmlInst, toXmlAttributeInst]

255246 Parser -> do

256− fromDomInst <- genFromDomInst

247+ fromDomInst <- genFromDomInst Strict

257248 fromAttributeInst <- genFromAttributeInst

258249 return $ enumDecls ++ [fromDomInst, fromAttributeInst]

259− Both -> do

250+ LenientParser -> do

251+ fromDomInst <- genFromDomInst Lenient

252+ fromAttributeInst <- genFromAttributeInst

253+ return $ enumDecls ++ [fromDomInst, fromAttributeInst]

254+ ParserAndGenerator -> do

260255 toXmlInst <- genToXmlInst

261256 toXmlAttributeInst <- genToXmlAttributeInst

262− fromDomInst <- genFromDomInst

257+ fromDomInst <- genFromDomInst Strict

258+ fromAttributeInst <- genFromAttributeInst

259+ return $ enumDecls ++ [toXmlInst, toXmlAttributeInst,

260+ fromDomInst, fromAttributeInst]

261+ LenientParserAndGenerator -> do

262+ toXmlInst <- genToXmlInst

263+ toXmlAttributeInst <- genToXmlAttributeInst

264+ fromDomInst <- genFromDomInst Lenient

263265 fromAttributeInst <- genFromAttributeInst

264266 return $ enumDecls ++ [toXmlInst, toXmlAttributeInst,

265267 fromDomInst, fromAttributeInst]

266268

267−isoXmlGenerateDatatype

268− :: GenType

269− -> GenerateLens

270− -> PrefixName

271− -> [IsoXmlDescRecordPart]

272− -> TH.DecsQ

273−isoXmlGenerateDatatype

274− genType

275− generateLens

276− (PrefixName strName' strPrefix')

277− descRecordParts = do

269+isoXmlGenerateDatatype :: GenType -> PrefixName -> [IsoXmlDescRecordPart] -> TH.DecsQ

270+isoXmlGenerateDatatype genType (PrefixName strName' strPrefix') descRecordParts = do

278271 let

279272 isNewtype = length descRecordParts == 1

280273 strName = "Xml" ++ strName'

281274 strPrefix = "x" ++ strPrefix'

282275 name = TH.mkName strName

283− fieldName str = case generateLens of

284− LensRenaming -> "_" ++ strPrefix ++ over _head C.toUpper str

285− NoLens -> str

276+ fieldName str = "_" ++ strPrefix ++ over _head C.toUpper str

286277 termDecl <- do

287278 let

288279 fields = do

@@ -293,11 +284,14 @@ isoXmlGenerateDatatype

293284 IsoXmlDescField fieldPlural rawName fieldType = descField

294285 fieldStrName = xmlLocalName rawName

295286 fName = TH.mkName (fieldName fieldStrName)

296− fType = case fieldPlural of

287+ fType' = case fieldPlural of

297288 XmlFieldPluralMandatory -> fieldType

298289 XmlFieldPluralOptional -> [t| Maybe $fieldType |]

299290 XmlFieldPluralRepeated -> [t| [$fieldType] |]

300291 XmlFieldPluralMultiplied -> [t| NonEmpty $fieldType |]

292+ fType = if isLenientType genType

293+ then [t| Maybe $fType' |]

294+ else fType'

301295 in if isNewtype

302296 then THC.varStrictType fName (THC.nonStrictType fType)

303297 else THC.varStrictType fName (THC.strictType fType)

@@ -332,7 +326,7 @@ isoXmlGenerateDatatype

332326 [ ]

333327

334328 let

335− genFromDomInst = do

329+ genFromDomInst mode = do

336330 let

337331 exprHeader = [e|pure $(TH.conE name)|]

338332 exprRecordParts = do

@@ -346,8 +340,9 @@ isoXmlGenerateDatatype

346340 fieldParse = case fieldPlural of

347341 XmlFieldPluralMandatory -> [e|inElem|]

348342 _ -> [e|inElemTrav|]

349− in

350− [e|$fieldParse $exprFieldStrName fromDom|]

343+ in case mode of

344+ Strict -> [e|$fieldParse $exprFieldStrName fromDom|]

345+ Lenient -> [e|$fieldParse $exprFieldStrName (ignoreBlank fromDom)|]

351346 IsoXmlDescRecordAttribute descAttribute ->

352347 let

353348 IsoXmlDescAttribute attributePlural attributeStrName _ = descAttribute

@@ -433,12 +428,21 @@ isoXmlGenerateDatatype

433428 return $ [termDecl] ++ lensDecls ++

434429 [toXmlInst, toXmlParentAttributesInst, nfDataInst]

435430 Parser -> do

436− fromDomInst <- genFromDomInst

431+ fromDomInst <- genFromDomInst Strict

437432 return $ [termDecl] ++ lensDecls ++ [fromDomInst, nfDataInst]

438− Both -> do

433+ LenientParser -> do

434+ fromDomInst <- genFromDomInst Lenient

435+ return $ [termDecl] ++ lensDecls ++ [fromDomInst, nfDataInst]

436+ ParserAndGenerator -> do

437+ toXmlInst <- genToXmlInst

438+ toXmlParentAttributesInst <- genToXmlParentAttributeInst

439+ fromDomInst <- genFromDomInst Strict

440+ return $ [termDecl] ++ lensDecls ++

441+ [fromDomInst, toXmlInst, toXmlParentAttributesInst, nfDataInst]

442+ LenientParserAndGenerator -> do

439443 toXmlInst <- genToXmlInst

440444 toXmlParentAttributesInst <- genToXmlParentAttributeInst

441− fromDomInst <- genFromDomInst

445+ fromDomInst <- genFromDomInst Lenient

442446 return $ [termDecl] ++ lensDecls ++

443447 [fromDomInst, toXmlInst, toXmlParentAttributesInst, nfDataInst]

444448

src/Text/XML/Nillable.hsnew file+41

@@ -0,0 +1,41 @@

1+{-# LANGUAGE MonoLocalBinds #-}

2+{-# LANGUAGE OverloadedStrings #-}

4+module Text.XML.Nillable where

6+import Control.DeepSeq

7+import Control.Lens

8+import Text.XML.DOM.Parser

9+import Text.XML.ParentAttributes

10+import Text.XML.Writer

11+

12+-- | Type that can have explicit null value

13+--

14+-- Null value is indicated by "nil"="true" attribute.

15+newtype Nillable a = Nillable (Maybe a)

16+ deriving

17+ ( Eq, Show, Ord, Read, NFData, ToXML

18+ , Functor, Applicative, Monad, Foldable, Traversable)

19+

20+_Nillable :: Prism' (Nillable a) a

21+_Nillable = coerced . _Just

22+

23+nNill :: Nillable a

24+nNill = Nillable Nothing

25+

26+nJust :: a -> Nillable a

27+nJust = Nillable . Just

28+

29+instance ToXmlParentAttributes a => ToXmlParentAttributes (Nillable a) where

30+ toXmlParentAttributes (Nillable Nothing) =

31+ [("{http://www.w3.org/2001/XMLSchema-instance}nil", "true")]

32+ toXmlParentAttributes (Nillable (Just a)) = toXmlParentAttributes a

33+

34+instance FromDom a => FromDom (Nillable a) where

35+ fromDom = do

36+ nil <- parseAttributeMaybe

37+ (matchName "{http://www.w3.org/2001/XMLSchema-instance}nil")

38+ Right

39+ case nil of

40+ Just "true" -> return (Nillable Nothing)

41+ _ -> Nillable . Just <$> fromDom

stack-10.0.yamlnew file+8

@@ -0,0 +1,8 @@

1+nix:

2+ packages:

3+ - zlib

5+resolver: lts-10.0

6+extra-deps:

7+- dom-parser-3.0.0

8+- generic-arbitrary-0.1.0

stack-18.18.yamlnew file+9

@@ -0,0 +1,9 @@

1+nix:

2+ packages:

3+ - zlib

5+resolver: lts-18.18

6+extra-deps:

7+- git: https://github.com/typeable/dom-parser.git

8+ commit: 7d556ba528bfa216e99714f8a0d4d00f452803a9

9+- xml-lens-0.3.1

stack-19.6.yamlnew file+9

@@ -0,0 +1,9 @@

1+nix:

2+ packages:

3+ - zlib

5+resolver: lts-19.6

6+extra-deps:

7+- git: https://github.com/typeable/dom-parser.git

8+ commit: 7d556ba528bfa216e99714f8a0d4d00f452803a9

9+- xml-lens-0.3.1

stack.yaml+8−3

@@ -1,4 +1,9 @@

1−resolver: lts-10.0

1+nix:

2+ packages:

3+ - zlib

5+resolver: lts-20.16

26extra-deps:

3−- dom-parser-3.0.0

4−- generic-arbitrary-0.1.0

7+ - git: https://github.com/typeable/dom-parser.git

8+ commit: 7d556ba528bfa216e99714f8a0d4d00f452803a9

9+ - xml-lens-0.3.1

test/TestDefs.hs+4−4

@@ -9,11 +9,11 @@ import Data.THGen.XML

99import Test.QuickCheck.Arbitrary.Generic

1010import Test.QuickCheck.Instances ()

1111

12−"Bar" =:= enum Both

12+"Bar" =:= enum ParserAndGenerator

1313 & "baroque"

1414 & "bartender"

1515

16−"Quux" Exhaustive =:= enum Both

16+"Quux" Exhaustive =:= enum ParserAndGenerator

1717 & "ALL"

1818 & "YOUR"

1919 & "BASE"

@@ -22,14 +22,14 @@ import Test.QuickCheck.Instances ()

2222 & "TO"

2323 & "US"

2424

25−"Foo" =:= record Both NoLens

25+"Foo" =:= record ParserAndGenerator

2626 ^ "Shmuux" [t|XmlQuux|]

2727 + "Bar"

2828 ? "Baz" [t|Text|]

2929 !% "Quux"

3030 ?% "Muux" [t|XmlQuux|]

3131

32−"Root" =:= record Both LensRename

32+"Root" =:= record ParserAndGenerator

3333 ! "{http://example.com/ns/my-namespace}Foo"

3434

3535instance Arbitrary XmlRoot where

xml-isogen.cabal+8−1

@@ -1,5 +1,5 @@

11name: xml-isogen

2−version: 0.3.1

2+version: 0.3.2

33synopsis: Generate XML-isomorphic types

44description:

55 TemplateHaskell generators for XML-isomorphic data types, including

@@ -32,7 +32,9 @@ library

3232 , Data.THGen.XML

3333 , Data.THGen.XML.Internal

3434 , Text.XML.ParentAttributes

35+ , Text.XML.Nillable

3536 other-modules: Data.THGen.Compat

37+ , Data.THGen.Orphans

3638 , Text.XML.DOM.Parser.Internal.Content

3739 build-depends: QuickCheck >= 2.8

3840 , base >=4.8 && <5

@@ -40,17 +42,22 @@ library

4042 , deepseq

4143 , lens >= 4.13

4244 , mtl >= 2.2

45+ , scientific

4346 , semigroups >= 0.18

4447 , template-haskell >= 2.10

4548 , text >= 1.2

4649 , xml-conduit >= 1.0

4750 , xml-conduit-writer >= 0.1

4851

52+ ghc-options: -Wall

53+

4954 hs-source-dirs: src

5055

5156 default-language: Haskell2010

5257 default-extensions: CPP

58+ , DeriveTraversable

5359 , FlexibleInstances

60+ , GeneralizedNewtypeDeriving

5461 , LambdaCase

5562 , TemplateHaskell

5663 , TupleSections