{- |

Module : $Header$

Copyright : (c) Klaus L�ttich, Christian Maeder, and Uni Bremen 2002-2003

Licence : All rights reserved.

Maintainer : hets@tzi.de

Stability : provisional

Portability : portable

These datastructures describe the Annotations of (Het)CASL.

There is also a paramterized data type for an 'Annoted' 'item'.

-}

module Common.AS_Annotation where

import Common.Id

-- DrIFT command

{-! global: UpPos !-}

-- | start of an annote with its WORD or a comment

data Annote_word = Annote_word String | Comment_start deriving (Show, Eq)

-- | line or group for 'Unparsed_anno'

data Annote_text = Line_anno String | Group_anno [String] deriving (Show, Eq)

-- | formats to be displayed (may be extended in the future).

-- Drop 3 from the show result to get the string for parsing and printing

data Display_format = DF_HTML | DF_LATEX | DF_RTF

deriving (Show, Eq, Ord)

-- | swap a pair

swap :: (a, b) -> (b, a)

swap (a, b) = (b, a)

-- | swap the entries of a lookup table

swapTable :: [(a, b)] -> [(b, a)]

swapTable = map swap

-- | drop the first 3 characters from the show result

toTable :: (Show a) => [a] -> [(a, String)]

toTable = map $ \a -> (a, drop 3 $ show a)

-- | a lookup table for the textual representation of display formats

display_format_table :: [(Display_format, String)]

display_format_table = toTable [ DF_HTML, DF_LATEX, DF_RTF ]

-- | precedence 'Lower' means less and 'BothDirections' means less and greater.

-- 'Higher' means greater but this is syntactically not allowed in 'Prec_anno'.

-- 'NoDirection' can also not be specified explicitly,

-- but covers those ids that are not mentionend in precedences.

data PrecRel = Higher | Lower | BothDirections | NoDirection

deriving (Show, Eq)

-- | either left or right associative

data AssocEither = ALeft | ARight deriving (Show,Eq)

-- | semantic (line) annotations without further information.

-- Use the same drop-3-trick as for the 'Display_format'.

data Semantic_anno = SA_cons | SA_def | SA_implies | SA_mono

deriving (Show, Eq)

-- | a lookup table for the textual representation of semantic annos

semantic_anno_table :: [(Semantic_anno, String)]

semantic_anno_table = toTable [SA_cons, SA_def, SA_implies, SA_mono]

-- | all possible annotations (without comment-outs)

data Annotation = -- | constructor for comments or unparsed annotes

Unparsed_anno Annote_word Annote_text [Pos]

-- | known annotes

| Display_anno Id [(Display_format, String)] [Pos]

-- postion of anno start, keywords and anno end

| List_anno Id Id Id [Pos]

-- postion of anno start, commas and anno end

| Number_anno Id [Pos]

-- postion of anno start, commas and anno end

| Float_anno Id Id [Pos]

-- postion of anno start, commas and anno end

| String_anno Id Id [Pos]

-- postion of anno start, commas and anno end

| Prec_anno PrecRel [Id] [Id] [Pos]

-- ^ positions: "{",commas,"}", RecRel, "{",commas,"}"

-- | Lower = "< " BothDirections = "<>"

| Assoc_anno AssocEither [Id] [Pos] -- position of commas

| Label [String] [Pos]

-- postion of anno start and anno end

-- All annotations below are only as annote line allowed

| Semantic_anno Semantic_anno [Pos]

-- position information for annotations is provided

-- by every annotation

deriving (Show,Eq)

-- | an item wrapped in preceeding (left 'l_annos')

-- and following (right 'r_annos') annotations.

-- 'opt_pos' should carry the position of an optional semicolon

-- following a formula (but is currently unused).

data Annoted a = Annoted { item::a, opt_pos :: [Pos]

, l_annos, r_annos::[Annotation]}

deriving (Show, Eq)

-- | change the 'item'

mapAnnoted :: (a -> b) -> Annoted a -> Annoted b

mapAnnoted f (Annoted i o l r) = Annoted (f i) o l r

-- | add further following annotations

appendAnno :: Annoted a -> [Annotation] -> Annoted a

appendAnno (Annoted x p l r) y = Annoted x p l (r++y)

-- | put together preceding annotations and an item

addLeftAnno :: [Annotation] -> a -> Annoted a

addLeftAnno l i = Annoted i [] l []

-- | get the label following (or to the right of) an 'item'

getRLabel :: Annoted a -> String

getRLabel a = let ls = filter isLabel (r_annos a) in

if null ls then "" else

let Label l _ = head ls

in if null l then "" else head l

-- might be a multiline label

-- maybe remove white spaces

-- |

-- 'isLabel' tests if the given 'Annotation' is a label

-- (a 'Label' typically follows a formula)

isLabel :: Annotation -> Bool

isLabel a = case a of

Label _ _ -> True

_ -> False

-- |

-- 'isSemanticAnno' tests if the given 'Annotation' is a semantic one

isSemanticAnno :: Annotation -> Bool

isSemanticAnno a = case a of

Semantic_anno _ _ -> True

_ -> False

-- |

-- 'isComment' tests if the given 'Annotation' is a comment line or a

-- comment group

isComment :: Annotation -> Bool

isComment c = case c of

Unparsed_anno Comment_start _ _ -> True

_ -> False

-- |

-- 'isAnnote' is the invers function to 'isComment'

isAnnote :: Annotation -> Bool

isAnnote = not . isComment