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|
module Options ( Format(..), Flag(..)
, lookahead, prefix, suffix, verbose, options )
where
import Base
import GetOpt
import Char
import IO
data Format = Standard | Compact | Stackless | GVStack
deriving (Eq)
data Flag = Backtrack
| Code Format
| Copying
| Debug
| Expected
| GHC
| Help
| Info
| Lookahead Int
| Lexer
| Noinline
| Optimize
| Pagewidth Int
| Prefix String
| Signature Bool -- `|True|' means polymorphic
| Suffix String
| Trace
| Verbose
| Version
| Warranty
deriving (Eq)
lookahead :: [Flag] -> Int
lookahead opts = head ([ k | Lookahead k <- opts ] ++ [1]) `max` 1
prefix :: [Flag] -> String
prefix opts = head ([ s | Prefix s <- opts ] ++ [""])
suffix :: [Flag] -> String
suffix opts = head ([ s | Suffix s <- opts ] ++ ["__"])
verbose :: [Flag] -> String -> IO ()
verbose opts s
| Verbose `elem` opts = hPutStrLn stdout s
| otherwise = return ()
options :: [OptDescr Flag]
options = [ Option "b" ["backtrack"] (NoArg Backtrack)
"generate a backtracking parser"
, Option "c" ["code"] (OptArg getCode "compact|gvstack|stackless|standard")
"select output format"
, Option "" ["copying"] (NoArg Copying)
"display details of copying"
, Option "d" ["debug"] (NoArg Debug)
"emit debugging information"
, Option "e" ["expected"] (NoArg Expected)
"pass a list of expected terminals to `frown'"
, Option "g" ["ghc"] (NoArg GHC)
"use GHC extensions"
, Option "h?" ["help"] (NoArg Help)
"print this information"
, Option "i" ["info"] (NoArg Info)
"put additional information into generated file"
, Option "k" ["lookahead"] (OptArg getLookahead "nat")
"use k tokens of lookahead"
, Option "l" ["lexer"] (NoArg Lexer)
"use a monadic lexer (`get :: M Terminal')"
, Option "n" ["noinline"] (NoArg Noinline)
"generate NOINLINE pragmas"
, Option "o" ["optimize"] (NoArg Optimize)
"optimize parser"
, Option "p" ["pagewidth"] (OptArg getPagewidth "nat")
"use the specified pagewidth for pretty printing"
, Option "" ["prefix"] (OptArg getPrefix "string")
"use prefix for frown generated variables"
, Option "s" ["signature"] (OptArg getSignature "mono|poly")
"add type signatures"
, Option "" ["suffix"] (OptArg getSuffix "string")
"use suffix for frown generated variables"
, Option "t" ["trace"] (NoArg Trace)
"insert calls to tracing routines (`shift', `reduce' and `accept')"
, Option "v" ["verbose"] (NoArg Verbose)
"be verbose"
, Option "" ["version"] (NoArg Version)
"print version information"
, Option "" ["warranty"] (NoArg Warranty)
"display details of warranty" ]
getCode, getLookahead, getPagewidth, getPrefix, getSuffix, getSignature
:: Maybe String -> Flag
getCode Nothing = Code Standard
getCode (Just s)
| s << "compact" = Code Compact
| s << "gvstack" = Code GVStack
| s << "stackless" = Code Stackless
| otherwise = Code Standard
getLookahead Nothing = Lookahead 2
getLookahead (Just s) = Lookahead (read s)
getPagewidth Nothing = Pagewidth 80
getPagewidth (Just s) = Pagewidth (read s)
getPrefix Nothing = Prefix ""
getPrefix (Just s) = Prefix s
getSuffix Nothing = Suffix ""
getSuffix (Just s) = Suffix s
getSignature Nothing = Signature False
getSignature (Just s)
| s << "mono" = Signature False
| s << "poly" = Signature True
| otherwise = Signature False
(<<) :: String -> String -> Bool
s << t = map toLower s `isPrefix` map toLower t
|
