diff --git a/IndentParser.cabal b/IndentParser.cabal new file mode 100644 --- /dev/null +++ b/IndentParser.cabal @@ -0,0 +1,22 @@ +Name: IndentParser +Version: 0.1 +License: GPL +License-File: gplv3 +Maintainer:login id is ppk and host is cse dot iitk dot ac dot in +Author: Piyush P Kurur +Homepage: http://www.cse.iitk.ac.in/~ppk +Category: Parsing +Build-Depends: base, parsec +Synopsis: Combinators for parsing indentation based syntatic structures +Description: This package exposes two modules, + 'Text.ParserCombinators.Parsec.IndentParser' and + 'Text.ParserCombinators.Parsec.IndentToken', for constructing parser + combinators for indentation based syntactic structures. The former + exports the basic indentation parser combinators and + the later together with 'Text.ParserCombinators.Parsec.Language' and + 'Text.ParserCombinators.Parsec.Token' can be used to define tokenisers + for programming languages. +Exposed-modules: + Text.ParserCombinators.Parsec.IndentParser + Text.ParserCombinators.Parsec.IndentToken +Extra-Source-Files: TODO diff --git a/Setup.lhs b/Setup.lhs new file mode 100644 --- /dev/null +++ b/Setup.lhs @@ -0,0 +1,7 @@ +#!/usr/bin/runhaskell + + +> +> import Distribution.Simple +> main = defaultMain +> diff --git a/TODO b/TODO new file mode 100644 --- /dev/null +++ b/TODO @@ -0,0 +1,12 @@ +TODO + +* Lots of testing with actual parsers. +* Should the interface change ? +* Are there other indentation based syntactic structure + that have to be supported ? + + +This is the very first version. I am releasing to get important +feedback. The most important item in the todo list is obviously +testing the library. Also some research needs to be done on whether +one needs to change the interface, better names for combinators etc. diff --git a/Text/ParserCombinators/Parsec/IndentParser.hs b/Text/ParserCombinators/Parsec/IndentParser.hs new file mode 100644 --- /dev/null +++ b/Text/ParserCombinators/Parsec/IndentParser.hs @@ -0,0 +1,393 @@ + +{- + +Haskell module for constructing indentation aware parser combinators. +Copyright (C) 2007 Piyush P Kurur, + +This program is free software: you can redistribute it and/or modify +it under the terms of the GNU General Public License as published by +the Free Software Foundation, either version 3 of the License, or +(at your option) any later version. + +This program is distributed in the hope that it will be useful, +but WITHOUT ANY WARRANTY; without even the implied warranty of +MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +GNU General Public License for more details. + +You should have received a copy of the GNU General Public License +along with this program. If not, see . + + +-} + +{-| + +A module to construct indentation aware parsers. Many programming +language have indentation based syntax rules e.g. python and Haskell. +This module exports combinators to create such parsers. + +The input source can be thought of as a list of tokens. Abstractly +each token occurs at a line and a column and has a width. The column +number of a token measures is indentation. If t1 and t2 are two tokens +then we say that indentation of t1 is more than t2 if the column +number of occurrence of t1 is greater than that of t2. + +Currently this module supports two kind of indentation based syntactic +structures which we now describe: + +[Block] A block of indentation /c/ is a sequence of tokens with +indentation at least /c/. Examples for a block is a where clause of +Haskell with no explicit braces. + +[Line fold] A line fold starting at line /l/ and indentation /c/ is a +sequence of tokens that start at line /l/ and possibly continue to +subsequent lines as long as the indentation is greater than /c/. Such +a sequence of lines need to be /folded/ to a single line. An example +is MIME headers. Line folding based binding separation is used in +Haskell as well. + + +Warning: + +Internally indentations are implemented using Parser states. If one +wants to use parser states as well then use the 'getState' and +'setState' functions exported by this module instead of those exported +from the parsec library. Also use the 'parseTest' and 'runParser' +function exported from this module instead of the one exported from +Parsec. + + +-} + +module Text.ParserCombinators.Parsec.IndentParser + ( + -- * Parser type + + IndentParser, + -- * Parser Combinators. + -- $combinators + indentParser, + noIndent, block, lineFold, + betweenOrBlock, betweenOrLineFold, + -- * Primitive Parsers + -- $prim + IndentMode(..), + IndentState, state, indentMode, + saveIndentMode, + getIndentMode, setIndentMode, + -- * User state manipulation. + -- $state + getState, setState, + -- * Testing and Running. + -- $run + runParser, parseTest, + -- +) where + + + + +-- The functions @getState@ @setState@ and parseTest for indentation +-- Parsers are exported by this module. Hence they are hidden. + + +import Text.ParserCombinators.Parsec hiding ( + getState, + setState, + parseTest, + runParser + ) + +import Text.ParserCombinators.Parsec.Pos +import qualified Text.ParserCombinators.Parsec.Prim as PP +import Control.Monad(fmap) + +getStatePrim = PP.getState +setStatePrim = PP.setState +runParserPrim = PP.runParser + + +{-| + + An indentation aware parser. The parser should be of this type to + make it possible to parse indentation based grammatical structure. + +-} + + +type IndentParser tok st a = GenParser tok (IndentState st) a + + +{- $combinators + +The module exports three combinators are @'indentParser'@, @'block'@ +and @'lineFold'@. To construct parsers for indentation based grammars +one typically applies the @'indentParser'@ to all tokenisers. In +conjunction with @'Text.ParserCombinators.Parsec.Token'@ module, one +would want to apply indentParser to all the fields of the +'Text.ParserCombinators.Parsec.Token.TokenParser' record except +@'Text.ParserCombinators.Parsec.Token.whiteSpace'@. A block can then +be parsed using the combinator @'block'@ and a line fold using +@'lineFold'@. To generate indentation aware tokeniser from the +corresponding 'Text.ParserCombinators.Parsec.Language.LanguageDef' +record see the module @'Text.ParserCombinators.Parsec.IndentToken'@. + + + +-} + + + + +{-| + + The combinator indentParser makes its input parser indentation + aware. Usually one would want to make all the tokenisers indentation + aware. + +-} +indentParser :: IndentParser tok st a -> IndentParser tok st a +indentParser p = do indMode <- getIndentMode + case indMode of + NoIndent -> p -- + Block c -> blockP c p + LineFold l c -> lineP l c p + where blockP c p = do col <- column + if col >= c then p else pzero + lineP l c p = do col <- column + if col > c then p else + do ln <- line + if ln == l then p else pzero + + + + + +{-| + +The parser @`noIndent` p@ runs @p@ ignoring any indentation based +structure. This can be used to parse for example an explicitly braced +where clause in Haskell. + + + +-} + +noIndent :: IndentParser tok st a -> IndentParser tok st a +noIndent p = saveIndentMode $ do {setIndentMode NoIndent; p} + + + +{-| + +The parser @'block' p@ parses a /block/ of @p@ with the block +indentation being the current column number. + + +-} + +block :: IndentParser tok st a -> IndentParser tok st a +block p = saveIndentMode $ do col <- column + setIndentMode $ Block col + p + +{-| + +The parser @lineFold p@ parses a folded line of @p@. The current line +is the starting line. The indentation of the line depends on where in +the source we are. If we are in a block then the indentation is the +indentation of the block. Otherwise the current column is the +indentation. + +-} + +lineFold :: IndentParser tok st a -> IndentParser tok st a +lineFold p = saveIndentMode $ do ln <- line + indMode <- getIndentMode + case indMode of + NoIndent -> do col <- column + setIndentMode $ LineFold ln col + Block c -> setIndentMode $ LineFold ln c + p + + + +{-| + + The parser @betweenOrBlock open close p@ parses @p@ between @open@ +and @close@. If open is matched @p@ is parsed in 'NoIndent' mode otherwise +a block @p@ is parsed in 'Block' mode. For eg. the parser for parsing +haskell where clause would look like + +> whereClause = do reserved where; betweenOrBlock bindings + +-} +betweenOrBlock :: IndentParser tok st open -> + IndentParser tok st close -> + IndentParser tok st a -> + IndentParser tok st a + +betweenOrBlock left right p = do left; x <- noIndent p; right; return x + <|> block p + +{-| + +Similar to betweenOrBlock but uses lineFold instead of block. + +-} +betweenOrLineFold :: IndentParser tok st open -> + IndentParser tok st close -> + IndentParser tok st a -> + IndentParser tok st a +betweenOrLineFold left right p = do left; x <- noIndent p; right; return x + <|> lineFold p + + +-- | This returns the current line number + +line :: GenParser tok st Line +line = fmap sourceLine getPosition + +-- | This returns the current column number + +column :: GenParser tok st Column +column = fmap sourceColumn getPosition + + + +{- $prim + +We now describe the primitives that are used to build the combinators +@block@, @noIndent@ and @lineFold@. An indentation parser can be in +one of the following modes: + +[@NoIndent@] In this mode the parser ignores all indentation +constraints. All tokens regardless of their indentation are accepted. + +[@Block c@] In this mode a parser accepts only tokens which have +indentation at least @c@. A parser parsing a block that is indented +more than @c@ columns will be this mode. + +[@LineFold l c@] In this mode a parser accepts tokens as long as it is +in the current line or is indented more than @c@. When parsing a +folded line starting at @l@ and indentation more than @c@ the parser +will be in this mode. + + +-} + +data IndentMode = NoIndent + | Block Column + | LineFold Line Column deriving (Show, Eq) + + + +-- | This parser returns the current indentation mode. + + +getIndentMode :: IndentParser tok st IndentMode +getIndentMode = fmap indentMode getStatePrim + + +-- | This parser sets the current indentation mode + +setIndentMode :: IndentMode -> IndentParser tok st () +setIndentMode ind = do indState <- getStatePrim + PP.setState $ indState {indentMode = ind} + + +{-| + +The parser @saveIndentMode p@ saves the current indentation mode and +returns the result of running @p@. It restores back the old +indentation once @p@ has finished executing. + +-} +saveIndentMode :: IndentParser tok st a -> IndentParser tok st a +saveIndentMode p = do indMode <- getIndentMode + x <- p + setIndentMode indMode + return x + + + +{- $state + +Indentation awareness is built into indentation parser by using these +parser states. To distinguish it from the actual user defined state we +call the former the indentation state and the later the user state. + + + + + +-} + +-- | The parser state used by Indentation Parsers. + +data IndentState st = IndentState { + state :: st, -- the actual state + indentMode :: IndentMode -- the indentation mode + } + + + +-- | Gets the current user state. Use this instead of the one exported +-- from Parsec module + +getState :: IndentParser tok st st +getState = fmap state getStatePrim + + +{-| + +This parser sets the current state of the parser to the given input +state. Use this function instead of the one exported by the parsec +library. + +-} + +setState :: st -> IndentParser tok st () +setState st = do indState <- getStatePrim + PP.setState indState {state = st} + + + + + + +{- $run + + +The most generic way to run an IndentParser. Use @parseTest@ for +testing your parser instead. + +-} +runParser :: IndentParser tok st a -- ^ the parser to be run + -> st -- ^ the initial state + -> IndentMode -- ^ the indentation mode + -> SourceName -- ^ the source file name + -> [tok] -- ^ the list of tokens + -> Either ParseError a -- ^ the result of parsing + +runParser p st imode = runParserPrim p (IndentState st imode) + + + + +{-| + +This is the function analogues to parseTest of the Parsec module. +Given an indent parser @p :: IndentParser tok () a@ and a list of +tokens it runs the parser and prints the result. + +-} + + +parseTest :: Show a => IndentParser tok () a -> [tok] -> IO () +parseTest p input = case result of + Left err -> do putStr "Error"; print err + Right a -> do print a + where result = runParser p () NoIndent "" input + + diff --git a/Text/ParserCombinators/Parsec/IndentToken.hs b/Text/ParserCombinators/Parsec/IndentToken.hs new file mode 100644 --- /dev/null +++ b/Text/ParserCombinators/Parsec/IndentToken.hs @@ -0,0 +1,601 @@ +{-# OPTIONS_GHC -fglasgow-exts #-} + +{- + +Haskell module for constructing indentation aware parser combinators. +Copyright (C) 2007 Piyush P Kurur, + +This program is free software: you can redistribute it and/or modify +it under the terms of the GNU General Public License as published by +the Free Software Foundation, either version 3 of the License, or +(at your option) any later version. + +This program is distributed in the hope that it will be useful, +but WITHOUT ANY WARRANTY; without even the implied warranty of +MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +GNU General Public License for more details. + +You should have received a copy of the GNU General Public License +along with this program. If not, see . + + +-} + +{-| + +A module for constructing indentation aware tokeniser that can be used +in conjuction with @'Text.ParserCombinators.Parsec.Token'@. All the +combinator takes a @'Text.ParserCombinators.Parsec.Token.TokenParser'@ +as its first argument. For every field @foo@ of +@'Text.ParserCombinators.Parsec.Token.TokenParser'@ this module +exports a combinator @foo@. To define a tokeniser for an indentation +based language a user first defines the appropriate +@'Text.ParserCombinators.Parsec.Language.LanguageDef'@ record, applies +the combinator @'Text.ParserCombinators.Parsec.Token.makeTokenParser'@ +to get a @'Text.ParserCombinators.Parsec.Token.TokenParser'@ record +say @tokP@ and then, instead of selecting the field @foo@ of @tokP@, +applies the combinator @foo@ exported from this module to @tokP@. The +semantics of the combinator @foo@ is essentially same as that of the +field @foo@ of @'Text.ParserCombinators.Parsec.Token.TokenParser'@ but +the returned parsers are indentation aware. Apart from these there are +certain new combinators that are defined specifically for parsing +certain indentation based syntactic constructs. (We have not defined +squares use brackets instead) + + +There are two important classes of parser combinator exported by this +module: + +[Grouping Parser Combinator] A grouping parser combinator takes as +input a parser say @p@ and returns a parser that parses @p@ between +two /grouping delimiters/. There are three flavours of grouping +parsers: @foo@, @fooOrBlock@ and @fooOrLineFold@ where @foo@ can be +one of @'angles'@, @'braces'@, @'parens'@, @'brackets'@ or To +illustrate we take @foo@ to be braces. The parser @braces tokP p@ +parses @p@ delimited by '{' and '}'. In this case @p@ does not care +about indentation (i.e. the parser @p@ is run in +@'Text.ParserCombinators.Parsec.IndentParser.NoIndent'@ mode). The +parser @'bracesOrBlock' tokP p@ is like @braces tokP p@ but if no +explicit delimiting braces are given parses @p@ within an indented +block. Similarly @'bracesOrLineFold' tokP p@ parses @p@ between '{' +and '}' and uses line fold when no explicit braces are given. These +can be two varients can be defined as follows + +> bracesOrBlock tokP p = braces tokP $ noIndent p <|> block p +> bracesOrLineFold tokP p = braces tokP $ noIndent p <|> lineFold p + + +[Seperator Parser Combinator] A seperator parser combinator takes as +input a parser say @p@ and returns a parser that parses a list of @p@ +seperated by a seperator. The module exports the combinators @fooSep@, +@fooSep1@, @fooOrNewLineSep@ and @fooOrNewLineSep1@, where @foo@ is +either @semi@ (in which case the seperator is a semicolon ';') or +@comma@ (in which case the seperator is a comma ','). + + +To illustrate the use of this module we now give, as an incomplete +example, a parser that parses a where clause in Haskell which +illustrates the use of this module. + + +> import qualified Text.ParserCombinators.Parsec.Language as L +> import qualified Text.ParserCombinators.Parsec.Toke as T +> import qualified Text.ParserCombinator.Parsec.IndentToken as IT + + +> tokP = T.makeTokenParser L.haskellDef +> semiOrNewLineSep = IT.semiOrNewLineSep tokP +> bracesOrBlock = IT.bracesOrBlock tokP +> identifier = IT.identifier tokP +> .... +> symbol = IT.symbol tokP + +> binding = semiOrNewLineSep bind +> bind = do id <- identifier +> symbol (char '=') +> e <- expr +> return (id,e) +> whereClause = do reserved "where"; braceOrBlock binding + + +-} + + +module Text.ParserCombinators.Parsec.IndentToken + ( + -- * Types + IndentCharParser, + LanguageDef, + TokenParser, + -- * Combinators + identifier, reserved, + operator, reservedOp, + charLiteral, stringLiteral, + natural, integer, float, naturalOrFloat, + decimal, hexadecimal, octal, + semi, colon, dot, + lexeme, symbol, whiteSpace, + -- * Separator parser combinators + semiSep, semiSep1, commaSep, commaSep1, + semiOrNewLineSep, semiOrNewLineSep1, + commaOrNewLineSep, commaOrNewLineSep1, + -- * Grouping parser combinator + parens,parensOrBlock, parensOrLineFold, + braces, bracesOrBlock, bracesOrLineFold, + angles, anglesOrBlock, anglesOrLineFold, + brackets, bracketsOrBlock, bracketsOrLineFold + ) where + +import Text.ParserCombinators.Parsec hiding ( + getState, + setState, + parseTest, + runParser + ) + +import qualified Text.ParserCombinators.Parsec.Token as T +import qualified Text.ParserCombinators.Parsec.Language as L +import Text.ParserCombinators.Parsec.IndentParser + +type IndentCharParser st a = IndentParser Char st a +type LanguageDef st = L.LanguageDef (IndentState st) +type TokenParser st = T.TokenParser (IndentState st) + + + + +{-| Indentation aware parser to match a valid identifier of the +language. -} + +identifier :: TokenParser st -> IndentCharParser st String +identifier = indentParser . T.identifier + + +{-| Indentation aware parser to match a reserved word of the language. +-} + +reserved :: TokenParser st -> + String -- ^ The reserved word to be matched. + -> IndentCharParser st () +reserved tokP = indentParser . T.reserved tokP + + +{-| The parser @reserved tokP keyword@ parses the reserved word keyword. + The string keyword should have been declared as a reserved word in the + @'Text.ParserCombinator.Parserc.Language.LanguageDef'@ + -record. -} + +operator :: TokenParser st -> IndentCharParser st String +operator = indentParser . T.operator + +{-| + Indentation aware parser to match a reserved operator of the language. +-} + +reservedOp :: TokenParser st -> + String + -- ^ The reserved operator to be matched. Should have + -- been declared as a reserved operator in the + -- @'Text.ParserCombinator.Parserc.Language.LanguageDef'@ + -- record. + -> IndentCharParser st () + +reservedOp tokP = indentParser . T.reservedOp tokP + + + + + +{-| Indentation aware parser to match a character literal (the syntax +is assumend to be that of Hasekell which matches that of most +programming language). +-} + +charLiteral :: TokenParser st -> IndentCharParser st Char +charLiteral = indentParser . T.charLiteral + + + +{-| Indentation aware parser to match a string literal (the syntax is +assumend to be that of Hasekell which matches that of most programming +language). +-} + +stringLiteral :: TokenParser st -> IndentCharParser st String +stringLiteral = indentParser . T.stringLiteral + + +{-| Indentation aware parser to match a natural number. -} + +natural :: TokenParser st -> IndentCharParser st Integer +natural = indentParser . T.natural + +{-| + Indentation aware parser to match an integer. +-} + +integer :: TokenParser st -> IndentCharParser st Integer +integer = indentParser . T.integer + +{-| Indentation aware parser to match a floating point number. -} + +float :: TokenParser st -> IndentCharParser st Double +float = indentParser . T.float + +{-| Indentation aware parser to match either a natural number or +Floating point number. -} + +naturalOrFloat :: TokenParser st + -> IndentCharParser st (Either Integer Double) +naturalOrFloat = indentParser . T.naturalOrFloat + +-- | Indentation aware parser to match an integer in decimal. + + +decimal :: TokenParser st -> IndentCharParser st Integer +decimal = indentParser . T.decimal + +{-| Indentation aware parser to match an integer in hexadecimal.-} + +hexadecimal :: TokenParser st -> IndentCharParser st Integer +hexadecimal = indentParser . T.hexadecimal + +{-| + +Indentation aware parser to match an integer in ocatal. + +-} + +octal :: TokenParser st -> IndentCharParser st Integer +octal = indentParser . T.octal + + +{-| Matches a semicolon and returns ';'. -} + + +semi :: TokenParser st -> IndentCharParser st String +semi = indentParser . T.semi + +{-| Matches a comma and returns ",". -} + +comma :: TokenParser st -> IndentCharParser st String +comma = indentParser . T.comma + +{-| Matches a colon and returns ":". -} +colon :: TokenParser st -> IndentCharParser st String +colon = indentParser . T.colon + +{-| Matches a dot and returns "." -} +dot :: TokenParser st -> IndentCharParser st String +dot = indentParser . T.dot + + +{-| Given an indentation aware parser @p@ as argument @semiSep tokP@ + returns a parser that parses zero or more occurances of @p@ + seperated by semicolon (';') -} + +semiSep :: TokenParser st + -> IndentCharParser st a + -> IndentCharParser st [a] + +semiSep tokP p = p `sepBy` semicolon + where semicolon = semi tokP + + +{-| Given an indentation aware parser @p@ as argument @semiSep1 tokP@ + returns a parser that parses one or more occurances of @p@ seperated + by semicolon (';') -} + + +semiSep1 :: TokenParser st + -> IndentCharParser st a -- ^ The input Parser + -> IndentCharParser st [a] + +semiSep1 tokP p = p `sepBy1` semicolon + where semicolon = semi tokP + + + +{-| Given an indentation aware parser @p@ as argument @commaSep tokP@ + returns a parser that parses zero or more occurances of @p@ + seperated by comma (',') -} + +commaSep :: TokenParser st + -> IndentCharParser st a -- ^ The input Parser + -> IndentCharParser st [a] + +commaSep tokP p = p `sepBy` virgule + where virgule = comma tokP + + + + +{-| Given an indentation aware parser @p@ as argument @commaSep1 tokP@ + returns a parser that parses one or more occurances of @p@ seperated + by comma (',') -} + + +commaSep1 :: TokenParser st + -> IndentCharParser st a -- ^ The input Parser + -> IndentCharParser st [a] + +commaSep1 tokP p = p `sepBy1` virgule + where virgule = comma tokP + + + + +{-| + +Given an indentation aware parser @p@ as argument @semiOrNewLineSep1 +tokP@ returns a parser that parses one or more occurances of @p@ +seperated by either semicolons (';') or newline. To seperate multiple +occurance of @p@ in the same line use an explicit semicolon (';'). + +-} + +semiOrNewLineSep1 :: TokenParser st + -> IndentCharParser st a -- ^ The input Parser + -> IndentCharParser st [a] + +semiOrNewLineSep1 tokP p = do xs <- lineFold $ semiSep1 tokP p + rest <- semiOrNewLineSep tokP p + return (xs++rest) + + + +{-| + +Given an indentation aware parser @p@ as argument @semiOrNewLineSep +tokP@ returns a parser that parses zero or more occurances of @p@ +seperated by either semicolons (';') or newlines. To seperate multiple +occurance of @p@ in the same line use an explicit semicolon (';'). + +-} + +semiOrNewLineSep :: TokenParser st + -> IndentCharParser st a -- ^ The input Parser + -> IndentCharParser st [a] + +semiOrNewLineSep tokP p = semiOrNewLineSep1 tokP p <|> return [] + + + + + +{-| + +Given an indentation aware parser @p@ as argument @commaOrNewLineSep1 +tokP@ returns a parser that parses one or more occurances of @p@ +seperated by either comma (',') or newline. To seperate multiple +occurance of @p@ in the same line use an explicit comma (','). + +-} + +commaOrNewLineSep1 :: TokenParser st + -> IndentCharParser st a -- ^ The input Parser + -> IndentCharParser st [a] + +commaOrNewLineSep1 tokP p = do xs <- lineFold $ semiSep1 tokP p + rest <- semiOrNewLineSep tokP p + return (xs++rest) + + + +{-| + +Given an indentation aware parser @p@ as argument @commaOrNewLineSep +tokP@ returns a parser that parses zero or more occurances of @p@ +seperated by either comma (',') or newlines. To seperate multiple +occurance of @p@ in the same line use an explicit comma (','). + +-} + +commaOrNewLineSep :: TokenParser st + -> IndentCharParser st a -- ^ The input Parser + -> IndentCharParser st [a] + +commaOrNewLineSep tokP p = commaOrNewLineSep1 tokP p <|> return [] + + + +{-| + +The parser @parens tokP p@ parses @p@ between '(' and ')'. The parser +@p@ does not care about indentation i.e. @p@ is run in +@'Text.ParserCombinators.Parsec.IndentParser.NoIndent'@ mode. + +-} + +parens :: TokenParser st -> + IndentCharParser st a -- ^ The input Parser + -> IndentCharParser st a + +parens tokP p = between (symbol tokP "(") (symbol tokP ")") (noIndent p) + +{-| + +Similar to @'parens'@ but when no explicit '(' and ')' are given, +groups @p@ by block indentation. + +-} + +parensOrBlock :: TokenParser st -> + IndentCharParser st a -- ^ The input parser + -> IndentCharParser st a + +parensOrBlock tokP p = parens tokP p <|> block p + + + +{-| + +Similar to @'parens'@ but when no explicit '(' and ')' are given, +groups @p@ by a line fold. + +-} +parensOrLineFold :: TokenParser st -> + IndentCharParser st a -- ^ The input parser + -> IndentCharParser st a + +parensOrLineFold tokP p = parens tokP p <|> lineFold p + + +{-| + +The parser @braces tokP p@ parses @p@ between '{' and '}'. The parser +@p@ does not care about indentation i.e. @p@ is run in +@'Text.ParserCombinators.Parsec.IndentParser.NoIndent'@ mode. + +-} + +braces :: TokenParser st -> + IndentCharParser st a -- ^ The input Parser + -> IndentCharParser st a + +braces tokP p = between (symbol tokP "{") (symbol tokP "}") (noIndent p) + + + +{-| + +Similar to @'braces'@ but when no explicit '{' and '}' are given, +groups @p@ by block indentation. + +-} +bracesOrBlock :: TokenParser st -> + IndentCharParser st a -- ^ The input parser + -> IndentCharParser st a + +bracesOrBlock tokP p = braces tokP p <|> block p + + +{-| + +Similar to @'braces'@ but when no explicit '{' and '}' are given, +groups @p@ by a line fold. + +-} + +bracesOrLineFold :: TokenParser st -> + IndentCharParser st a -- ^ The input parser + -> IndentCharParser st a + +bracesOrLineFold tokP p = braces tokP p <|> lineFold p + + +{-| + +The parser @angles tokP p@ parses @p@ between angles. The parser @p@ +does not care about indentation i.e. @p@ is run in +@'Text.ParserCombinators.Parsec.IndentParser.NoIndent'@ mode. + +-} + +angles :: TokenParser st -> + IndentCharParser st a -- ^ The input Parser + -> IndentCharParser st a + +angles tokP p = between (symbol tokP "<") (symbol tokP ">") (noIndent p) + + + +{-| + +Similar to @'angles'@ but when no explicit angles are given, groups +@p@ by block indentation. + +-} + +anglesOrBlock :: TokenParser st -> + IndentCharParser st a -- ^ The input parser + -> IndentCharParser st a + +anglesOrBlock tokP p = angles tokP p <|> block p + + +{-| + +Similar to @'angles'@ but when no explicit angles are given, groups +@p@ by a line fold. + +-} + +anglesOrLineFold :: TokenParser st -> + IndentCharParser st a -- ^ The input parser + -> IndentCharParser st a + +anglesOrLineFold tokP p = angles tokP p <|> lineFold p + + + +{-| + +The parser @brackets tokP p@ parses @p@ between '[' and ']'. The +parser @p@ does not care about indentation i.e. @p@ is run in +@'Text.ParserCombinators.Parsec.IndentParser.NoIndent'@ mode. + +-} + +brackets :: TokenParser st -> + IndentCharParser st a -- ^ The input Parser + -> IndentCharParser st a + +brackets tokP p = between (symbol tokP "[") (symbol tokP "]") (noIndent p) + + + +{-| + +Similar to @'brackets'@ but when no explicit '[' and ']' are given, +groups @p@ by block indentation. + +-} +bracketsOrBlock :: TokenParser st -> + IndentCharParser st a -- ^ The input parser + -> IndentCharParser st a + +bracketsOrBlock tokP p = brackets tokP p <|> block p + + +{-| + +Similar to @'brackets'@ but when no explicit '[' and ']' are given, +groups @p@ by a line fold. + +-} + +bracketsOrLineFold :: TokenParser st -> + IndentCharParser st a -- ^ The input parser + -> IndentCharParser st a + +bracketsOrLineFold tokP p = brackets tokP p <|> lineFold p + + +{-| + +Indentation aware parser that is equvalent to string str. + +-} + +symbol :: TokenParser st + -> String + -> IndentCharParser st String +symbol tokP = indentParser . T.symbol tokP + + +{-| Creates a lexeme parser. The resultant parser skips trailing +spaces and is indentation aware. -} + +lexeme :: TokenParser st + -> IndentCharParser st a -- ^ The input parser. + -> IndentCharParser st a + +lexeme tokP = indentParser . T.lexeme tokP + +{-| The parser whiteSpace skips spaces and comments. This does not +care about indentation as skipping spaces should be done irrespective +of the indentation. -} + +whiteSpace :: TokenParser st -> IndentCharParser st () +whiteSpace = T.whiteSpace diff --git a/gplv3 b/gplv3 new file mode 100644 --- /dev/null +++ b/gplv3 @@ -0,0 +1,674 @@ + GNU GENERAL PUBLIC LICENSE + Version 3, 29 June 2007 + + Copyright (C) 2007 Free Software Foundation, Inc. + Everyone is permitted to copy and distribute verbatim copies + of this license document, but changing it is not allowed. + + Preamble + + The GNU General Public License is a free, copyleft license for +software and other kinds of works. + + The licenses for most software and other practical works are designed +to take away your freedom to share and change the works. By contrast, +the GNU General Public License is intended to guarantee your freedom to +share and change all versions of a program--to make sure it remains free +software for all its users. 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Disclaimer of Warranty. + + THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY +APPLICABLE LAW. EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT +HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY +OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, +THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR +PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM +IS WITH YOU. SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF +ALL NECESSARY SERVICING, REPAIR OR CORRECTION. + + 16. Limitation of Liability. + + IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING +WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS +THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY +GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE +USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF +DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD +PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS), +EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF +SUCH DAMAGES. + + 17. Interpretation of Sections 15 and 16. + + If the disclaimer of warranty and limitation of liability provided +above cannot be given local legal effect according to their terms, +reviewing courts shall apply local law that most closely approximates +an absolute waiver of all civil liability in connection with the +Program, unless a warranty or assumption of liability accompanies a +copy of the Program in return for a fee. + + END OF TERMS AND CONDITIONS + + How to Apply These Terms to Your New Programs + + If you develop a new program, and you want it to be of the greatest +possible use to the public, the best way to achieve this is to make it +free software which everyone can redistribute and change under these terms. + + To do so, attach the following notices to the program. It is safest +to attach them to the start of each source file to most effectively +state the exclusion of warranty; and each file should have at least +the "copyright" line and a pointer to where the full notice is found. + + + Copyright (C) + + This program is free software: you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation, either version 3 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see . + +Also add information on how to contact you by electronic and paper mail. + + If the program does terminal interaction, make it output a short +notice like this when it starts in an interactive mode: + + Copyright (C) + This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'. + This is free software, and you are welcome to redistribute it + under certain conditions; type `show c' for details. + +The hypothetical commands `show w' and `show c' should show the appropriate +parts of the General Public License. Of course, your program's commands +might be different; for a GUI interface, you would use an "about box". + + You should also get your employer (if you work as a programmer) or school, +if any, to sign a "copyright disclaimer" for the program, if necessary. +For more information on this, and how to apply and follow the GNU GPL, see +. + + The GNU General Public License does not permit incorporating your program +into proprietary programs. If your program is a subroutine library, you +may consider it more useful to permit linking proprietary applications with +the library. If this is what you want to do, use the GNU Lesser General +Public License instead of this License. But first, please read +.