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implementation module Clean.Doc

import _SystemArray
import StdBool
import StdChar
import StdDebug
from StdFunc import flip, o, twice
import StdList
import StdMisc
import StdOrdList
import StdString
import StdTuple

import Control.Applicative
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from Control.Monad import mapM, class Monad(..), >>=
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import Data.Either
import Data.Error
from Data.Func import $
import Data.Functor
import Data.GenDefault
import Data.List
import Data.Maybe
import Data.Tuple
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from Text import <+,
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	class Text(join,split,trim,rtrim,replaceSubString,endsWith,startsWith),
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	instance Text String, instance Text [Char]
import Text.Language
import Text.Parsers.Simple.ParserCombinators

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from Clean.Types import :: Type, :: TypeRestriction, :: TypeContext
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from Clean.Types.Parse import parseType
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from Clean.Types.Util import instance toString Type
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gDefault{|Maybe|} _ = Nothing

fromMultiLine :: !MultiLineString -> String
fromMultiLine (MultiLine s) = s

instance docDescription       ModuleDoc where docDescription       d = d.ModuleDoc.description
instance docPropertyBootstrap ModuleDoc where docPropertyBootstrap d = fromMultiLine <$> d.property_bootstrap
instance docPropertyTestWith  ModuleDoc where docPropertyTestWith  d = d.ModuleDoc.property_test_with
instance docPropertyTestGenerators ModuleDoc where docPropertyTestGenerators d = d.property_test_generators

instance docDescription      FunctionDoc where docDescription      d = d.FunctionDoc.description
instance docComplexity       FunctionDoc where docComplexity       d = d.FunctionDoc.complexity
instance docParams           FunctionDoc where docParams           d = d.FunctionDoc.params
instance docVars             FunctionDoc where docVars             d = d.FunctionDoc.vars
instance docResults          FunctionDoc where docResults          d = d.FunctionDoc.results
instance docType             FunctionDoc where docType             d = d.FunctionDoc.type
instance docThrows           FunctionDoc where docThrows           d = d.FunctionDoc.throws
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instance docProperties       FunctionDoc where docProperties       d = d.FunctionDoc.properties
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instance docPropertyTestWith FunctionDoc where docPropertyTestWith d = d.FunctionDoc.property_test_with
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instance docPreconditions    FunctionDoc where docPreconditions    d = d.FunctionDoc.preconditions

instance docDescription      InstanceDoc where docDescription      d = d.InstanceDoc.description
instance docComplexity       InstanceDoc where docComplexity       d = d.InstanceDoc.complexity
instance docProperties       InstanceDoc where docProperties       d = d.InstanceDoc.properties
instance docPropertyTestWith InstanceDoc where docPropertyTestWith d = d.InstanceDoc.property_test_with
instance docPreconditions    InstanceDoc where docPreconditions    d = d.InstanceDoc.preconditions
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instance docDescription ParamDoc where docDescription d = d.ParamDoc.description

instance docDescription ClassMemberDoc where docDescription d = d.ClassMemberDoc.description
instance docComplexity  ClassMemberDoc where docComplexity  d = d.ClassMemberDoc.complexity
instance docParams      ClassMemberDoc where docParams      d = d.ClassMemberDoc.params
instance docResults     ClassMemberDoc where docResults     d = d.ClassMemberDoc.results
instance docType        ClassMemberDoc where docType        d = d.ClassMemberDoc.type
instance docThrows      ClassMemberDoc where docThrows      d = d.ClassMemberDoc.throws

instance docDescription ConstructorDoc where docDescription d = d.ConstructorDoc.description
instance docParams      ConstructorDoc where docParams      d = d.ConstructorDoc.params

instance docDescription ClassDoc where docDescription d = d.ClassDoc.description
instance docVars        ClassDoc where docVars        d = d.ClassDoc.vars
instance docMembers     ClassDoc where docMembers     d = d.ClassDoc.members

instance docDescription    TypeDoc where docDescription    d = d.TypeDoc.description
instance docVars           TypeDoc where docVars           d = d.TypeDoc.vars
instance docFields         TypeDoc where docFields         d = d.TypeDoc.fields
instance docConstructors   TypeDoc where docConstructors   d = d.TypeDoc.constructors
instance docRepresentation TypeDoc where docRepresentation d = d.TypeDoc.representation

instance toString ParamDoc
where
	toString pd=:{name=Just n,description=Just d} = n +++ ": " +++ d
	toString {ParamDoc | description=Just d} = d
	toString _ = ""

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derive gDefault Type, TypeRestriction, ModuleDoc, FunctionDoc, InstanceDoc, TypeContext,
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	ClassMemberDoc, ConstructorDoc, ClassDoc, TypeDoc, Property,
	PropertyVarInstantiation, MultiLineString, PropertyTestGenerator, ParamDoc
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constructorToFunctionDoc :: !ConstructorDoc -> FunctionDoc
constructorToFunctionDoc d =
	{ FunctionDoc
	| gDefault{|*|}
	& description = d.ConstructorDoc.description
	, params      = d.ConstructorDoc.params
	}

functionToClassMemberDoc :: !FunctionDoc -> ClassMemberDoc
functionToClassMemberDoc d =
	{ ClassMemberDoc
	| description = d.FunctionDoc.description
	, complexity  = d.FunctionDoc.complexity
	, params      = d.FunctionDoc.params
	, results     = d.FunctionDoc.results
	, type        = d.FunctionDoc.type
	, throws      = d.FunctionDoc.throws
	}

addClassMemberDoc :: !ClassDoc !(Maybe ClassMemberDoc) -> ClassDoc
addClassMemberDoc d m = {d & members=d.members ++ [m]}

parseSingleLineDoc :: (String -> String)
parseSingleLineDoc = toString o trim o dropWhile ((==) '*') o fromString

parseDoc :: !String -> Either ParseError (!d, ![ParseWarning]) | docBlockToDoc{|*|} d
parseDoc s = docBlockToDoc{|*|} (Left [s])

generic docBlockToDoc d :: !(Either [String] DocBlock) -> Either ParseError (!d, ![ParseWarning])
docBlockToDoc{|String|} (Left []) = Left InternalNoDataError
docBlockToDoc{|String|} (Left ss) = Right (trim $ last ss, [])
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docBlockToDoc{|String|} _         = abort "error in docBlockToDoc{|String|}\n"
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docBlockToDoc{|[]|} fx (Left ss) = (\vws -> (map fst vws, flatten (map snd vws)) ) <$> mapM fx (map (Left o pure) ss)
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docBlockToDoc{|[]|} _  _         = abort "error in docBlockToDoc{|[]|}\n"
docBlockToDoc{|Maybe|} fx (Left [])    = Right (Nothing, [])
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docBlockToDoc{|Maybe|} fx ss=:(Left _) = appFst Just <$> fx ss
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docBlockToDoc{|Maybe|} _  _            = abort "error in docBlockToDoc{|Maybe|}\n"
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docBlockToDoc{|UNIT|} _ = Right (UNIT, [])
docBlockToDoc{|PAIR|} fx fy db=:(Right _) = liftA2 (\(x,ws) (y,ws`) -> (PAIR x y, ws ++ ws`)) (fx db) (fy db)
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docBlockToDoc{|PAIR|} _  _  _             = abort "error in docBlockToDoc{|PAIR|}\n"
docBlockToDoc{|FIELD of {gfd_name}|} fx (Right db) = case fx (Left [v \\ (k,v) <- db | k matches gfd_name]) of
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	Right (f, ws)            -> Right (FIELD f, ws)
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	Left InternalNoDataError -> Left (MissingField gfd_name)
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	Left e                   -> Left e
where
	(matches) infix 4 :: !String !String -> Bool
	(matches) k name =
		k` == name ||
		pluralise English k` == name ||
		k` == "return" && name == "result" ||
		k` == "return" && name == "results"
	where
		k` = {if (c == '-') '_' c \\ c <-: k}
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docBlockToDoc{|FIELD of {gfd_name}|} _ _ = abort "error in docBlockToDoc{|FIELD|}\n"
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docBlockToDoc{|RECORD|} fx (Left [s]) = case parseDocBlock s of
	Right (db, ws) -> case fx (Right db) of
		Right (v, ws`) -> Right (RECORD v, ws ++ ws`)
		Left e -> Left e
	Left e -> Left e
docBlockToDoc{|RECORD|} fx doc = appFst RECORD <$> fx doc
docBlockToDoc{|CONS|} fx doc = appFst CONS <$> fx doc
docBlockToDoc{|EITHER|} fl fr doc = case fl doc of
	Right (v, ws) -> Right (LEFT v, ws)
	Left e -> case fr doc of
		Right (v, ws) -> Right (RIGHT v, ws)
		Left _ -> Left e
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docBlockToDoc{|OBJECT|} fx doc = appFst (\x -> OBJECT x) <$> fx doc
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docBlockToDoc{|MultiLineString|} (Left [s]) = Right (MultiLine $ trimMultiLine $ split "\n" s, [])
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docBlockToDoc{|MultiLineString|} _          = abort "error in docBlockToDoc{|MultiLineString|}\n"
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docBlockToDoc{|ParamDoc|} (Left [s]) = case findName (fromString s) of
	Just (name,rest) -> Right (
		{ name        = Just $ toString name
		, description = case rest of
			[] -> Nothing
			_  -> Just $ toString rest
		}, [])
	_                -> Right ({name=Nothing, description=Just s}, [])
where
	findName cs
	# (name,cs) = span (\c -> isAlphanum c || c == '`') cs
	| not (isEmpty name) && not (isEmpty cs) && hd cs == ':'
		= Just (toString name, dropWhile isSpace (tl cs))
		= Nothing
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docBlockToDoc{|ParamDoc|} _ = abort "error in docBlockToDoc{|ParamDoc|}\n"
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docBlockToDoc{|Type|} (Left []) = Left InternalNoDataError
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docBlockToDoc{|Type|} (Left ss) = case [v \\ Just v <- map (parseType o fromString) ss] of
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	[] -> Left (UnknownError "no parsable type")
	vs -> Right (last vs, [])
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docBlockToDoc{|Type|} _ = abort "error in docBlockToDoc{|Type|}\n"
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docBlockToDoc{|Property|} (Left [s]) = let [signature:property] = split "\n" s in
		parseSignature signature >>= \(sig,ws1) ->
		parseProperty property >>= \(prop,ws2) ->
		Right (sig prop, ws1 ++ ws2)
where
	parseSignature :: !String -> Either ParseError (!String -> Property, ![ParseWarning])
	parseSignature s = case parse parser (fromString s) of
		Left es           -> Left (UnknownError "failed to parse property signature")
		Right (name,args) -> Right (ForAll name args, [])
	where
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		parser :: Parser Char (!String, ![(String, Type)])
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		parser = skipSpaces *>
			pMany (pSatisfy ((<>) ':')) >>= \name ->
			skipSpaces *> pToken ':' *>
			((skipSpaces *> pToken 'A' *> pToken '.' *>
			pMany
				(skipSpaces *>
				(liftA2 tuple
					(toString <$> pMany (pSatisfy (not o isSpace)))
					(pList [skipSpaces,pToken ':',pToken ':',skipSpaces] *> pTypeWithColonOrSemicolon)
				) <* skipSpaces)) <|> skipSpaces *> pure []) >>= \args ->
			pure (toString name, args)

		skipSpaces = pMany (pSatisfy isSpace) *> pYield undef
		pTypeWithColonOrSemicolon = (pMany (pSatisfy \c -> c <> ':' && c <> ';') <* pOneOf [':;'])
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			>>= \t -> case parseType t of
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				Nothing -> pError "type could not be parsed"
				Just t  -> pure t

	parseProperty :: ![String] -> Either ParseError (!String, ![ParseWarning])
	parseProperty ss = Right (trimMultiLine ss, [])
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docBlockToDoc{|Property|} _ = abort "error in docBlockToDoc{|Property|}\n"
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docBlockToDoc{|PropertyVarInstantiation|} (Left [s]) = case split "=" s of
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	[var:type:[]] -> case parseType (fromString type) of
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		Just t -> Right (PropertyVarInstantiation (trim var, t), [])
		Nothing -> Left (UnknownError "type could not be parsed")
	_ -> Left (UnknownError "property var instantiation could not be parsed")
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docBlockToDoc{|PropertyVarInstantiation|} _ = abort "error in docBlockToDoc{|PropertyVarInstantiation|}\n"
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docBlockToDoc{|PropertyTestGenerator|} (Left [s])
| startsWith "list: " sig = case parseType [c \\ c <-: sig & i <- [0..] | i > 4] of
	Just t  -> Right (PTG_List t imp, [])
	Nothing -> error
| otherwise = case parseType (fromString sig) of
	Just t  -> Right (PTG_Function t imp, [])
	Nothing -> error
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where
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	sig = trim sig`
	imp = trimMultiLine imp`
	[sig`:imp`] = split "\n" s
	error = Left (UnknownError "test generator could not be parsed")
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docBlockToDoc{|PropertyTestGenerator|} _ = abort "error in docBlockToDoc{|PropertyTestGenerator|}\n"
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derive docBlockToDoc ModuleDoc, FunctionDoc, InstanceDoc, ClassMemberDoc,
	ConstructorDoc, ClassDoc, TypeDoc
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printDoc :: !d -> String | docToDocBlock{|*|} d
printDoc d = join "\n * "
	[ "/**"
	: (case desc of
		Nothing -> []
		Just d  -> [replaceSubString "\n" "\n * " d] ++ (if (isEmpty fields) [] [""])) ++
	  ["@" +++ f +++ " " +++ replaceSubString "\n" "\n *   " v \\ (f,v) <- fields]
	] +++
	"\n */"
where
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	fields` = case docToDocBlock{|*|} False d of
		Right fs -> fs
		_        -> abort "error in printDoc\n"
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	fields = filter ((<>) "description" o fst) fields`
	desc = lookup "description" fields`

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generic docToDocBlock a :: !Bool !a -> Either [String] DocBlock
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docToDocBlock{|String|} True s = Left [s]
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docToDocBlock{|String|} _    _ = abort "error in docToDocBlock{|String|}\n"
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docToDocBlock{|[]|} fx True xs = Left [x \\ Left xs` <- map (fx True) xs, x <- xs`]
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docToDocBlock{|[]|} _  _    _  = abort "error in docToDocBlock{|[]|}\n"
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docToDocBlock{|Maybe|} fx True mb = case mb of
	Nothing -> Left []
	Just x  -> fx True x
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docToDocBlock{|Maybe|} _  _    _  = abort "error in docToDocBlock{|Maybe|}\n"

docToDocBlock{|PAIR|} fx fy False (PAIR x y) = case fx False x of
	Right xs -> case fy False y of
		Right ys -> Right (xs ++ ys)
		_        -> abort "error in docToDocBlock{|PAIR|}\n"
	_            -> abort "error in docToDocBlock{|PAIR|}\n"
docToDocBlock{|PAIR|} _  _  _      _         = abort "error in docToDocBlock{|PAIR|}\n"
docToDocBlock{|FIELD of d|} fx False (FIELD x) = case fx True x of
	Left xs -> Right [(name,x) \\ x <- xs]
	_       -> abort "error in docToDocBlock{|FIELD|}\n"
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where
	name = {if (c=='_') '-' c \\ c <-: name`}
	name`
	| endsWith "ies" d.gfd_name = d.gfd_name % (0,size d.gfd_name-4) +++ "y"
	| endsWith "s" d.gfd_name   = d.gfd_name % (0,size d.gfd_name-2)
	| otherwise                 = d.gfd_name
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docToDocBlock{|FIELD|} _ _ _ = abort "error in docToDocBlock{|FIELD|}\n"
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docToDocBlock{|RECORD|} fx False (RECORD x) = fx False x
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docToDocBlock{|RECORD|} _  _     _          = abort "error in docToDocBlock{|RECORD|}\n"
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docToDocBlock{|ParamDoc|} True pd = case pd.ParamDoc.name of
	Nothing -> case pd.ParamDoc.description of
		Nothing -> Left []
		Just d -> Left [d]
	Just n -> case pd.ParamDoc.description of
		Nothing -> Left [n]
		Just d -> Left [n +++ ": " +++ d]
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docToDocBlock{|ParamDoc|} _ _ = abort "error in docToDocBlock{|ParamDoc|}\n"
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docToDocBlock{|MultiLineString|} True (MultiLine s) = Left [s]
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docToDocBlock{|MultiLineString|} _    _             = abort "error in docToDocBlock{|MultiLineString|}\n"
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docToDocBlock{|Type|} True t = Left [toString t]
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docToDocBlock{|Type|} _    _ = abort "error in docToDocBlock{|Type|}\n"
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docToDocBlock{|Property|} True (ForAll name args impl) = Left
	[name +++ ": A." +++ join "; " [a +++ " :: " <+ t \\ (a,t) <- args] +++ ":\n" +++ impl]
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docToDocBlock{|Property|} _ _ = abort "error in docToDocBlock{|Property|}\n"
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docToDocBlock{|PropertyVarInstantiation|} True (PropertyVarInstantiation (a,t)) = Left [a +++ " = " <+ t]
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docToDocBlock{|PropertyVarInstantiation|} _    _                                = abort "error in docToDocBlock{|PropertyVarInstantiation|}\n"
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docToDocBlock{|PropertyTestGenerator|} True ptg = Left [t <+ "\n" +++ imp]
where
	(t,imp) = case ptg of
		PTG_Function t imp -> (t,imp)
		PTG_List t imp     -> (t,imp)
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docToDocBlock{|PropertyTestGenerator|} _    _                              = abort "error in docToDocBlock{|PropertyTestGenerator|}\n"
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derive docToDocBlock ModuleDoc, FunctionDoc, InstanceDoc, ClassMemberDoc,
	ClassDoc, ConstructorDoc, TypeDoc
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trimMultiLine :: ![String] -> String
trimMultiLine ss = join "\n" [s % (trimn, size s - 1) \\ s <- ss]
where
	trimn = minList [i \\ Just i <- map (firstNonSpace 0) ss]

	firstNonSpace :: !Int !String -> Maybe Int
	firstNonSpace i s
	| i >= size s   = Nothing
	| isSpace s.[i] = firstNonSpace (i+1) s
	| otherwise     = Just i

parseDocBlock :: !String -> Either ParseError (!DocBlock, ![ParseWarning])
parseDocBlock b = prepareString b >>= parsef
where
	parsef :: ![[Char]] -> Either ParseError (!DocBlock, ![ParseWarning])
	parsef [] = Right ([], [])
	parsef lines = case span (\l -> isEmpty l || hd l <> '@') lines of
		([],   [ln]) = parseFields [ln]
		([],   rest) = appSnd (\ws -> [NoDescription:ws]) <$> parseFields rest
		(desc, rest) = appFst (\d -> [("description", linesToString desc):d]) <$> parseFields rest

	parseFields :: ![[Char]] -> Either ParseError (!DocBlock, ![ParseWarning])
	parseFields []
		= Right ([], [])
	parseFields [['@':line]:rest]
		= parseFields rest` >>=
			\(d,ws) -> appSnd ((++) ws) <$> parseFs field desc d
	where
		(field, descline) = span (not o isSpace) line
		(restdesc, rest`) = span (\l -> isEmpty l || hd l <> '@') rest
		desc = flatten $ intersperse ['\n'] $ if (isEmpty descline) restdesc [tl descline:restdesc]

		parseFs :: ![Char] ![Char] !DocBlock -> Either ParseError (!DocBlock, ![ParseWarning])
		parseFs field val d = Right ([(toString field,toString (rtrim val)):d], [])
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	parseFields _
		= abort "error in parseDocBlock\n"
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prepareString :: (String -> Either ParseError [[Char]])
prepareString = checkAsterisks o map trim o break '\n' o fromString
where
	checkAsterisks :: ![[Char]] -> Either ParseError [[Char]]
	checkAsterisks [['*':line]] = Right [safetl line]
	checkAsterisks [line] = Right [line]
	checkAsterisks lines
	| all (\l -> isEmpty l || hd l == '*') lines
		= Right $ map (safetl o dropWhile ((==) '*')) lines
		= Left $ MissingAsterisk $ toString $ hd $ filter (\l -> not (isEmpty l) && hd l <> '*') lines

	safetl :: ![a] -> [a]
	safetl []     = []
	safetl [_:xs] = xs

	break :: !a -> [a] -> [[a]] | == a
	break e = foldr f []
	where
		f x []     = if (x == e) []        [[x]]
		f x [y:ys] = if (x == e) [[]:y:ys] [[x:y]:ys]

linesToString :: ([[Char]] -> String)
linesToString = toString o flatten o intersperse ['\n']

instance toString ParseWarning
where
	toString (UnknownField f)   = "Doc warning: unknown field '" +++ f +++ "'"
	toString (IllegalField f)   = "Doc warning: illegal field '" +++ f +++ "'"
	toString NoDescription      = "Doc warning: missing description"
	toString UsedReturn         = "Doc warning: @return is deprecated, use @result"
	toString (UnparsableType t) = "Doc warning: could not parse type '" +++ t +++ "'"

instance toString ParseError
where
	toString (MissingAsterisk l) = "Doc error: missing leading asterisk in '" +++ l +++ "'"
	toString (MissingField f)    = "Doc error: required field '" +++ f +++ "' was missing"
	toString (UnknownError e)    = "Doc error: " +++ e
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	toString InternalNoDataError = "Doc error: internal parsing error"
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traceParseWarnings :: ![ParseWarning] !a -> a
traceParseWarnings []     x = x
traceParseWarnings [w:ws] x
| trace_tn w = traceParseWarnings ws x
| otherwise  = undef

traceParseError :: !ParseError !a -> a
traceParseError e x
| trace_tn e = x
| otherwise  = undef