import System.Environment (getArgs)
--- Dark magic.
+-- | Lowercase an entire string.
lowercase :: String -> String
lowercase = map toLower
--- The application currently has three modes. The default, Regex, will
--- compute a regular expression matching the input CIDRs. Reduce, on
--- the other hand, will combine any redundant/adjacent CIDR blocks
--- into one. Dupe will show you what would be removed by Reduce.
-data Mode = Regex | Reduce | Dupe
+-- | The application currently has four modes. The default, Regex,
+-- will compute a regular expression matching the input
+-- CIDRs. Reduce, on the other hand, will combine any
+-- redundant/adjacent CIDR blocks into one. Dupe will show you what
+-- would be removed by Reduce, and Diff will show both additions and
+-- deletions in a diff-like format.
+data Mode = Regex | Reduce | Dupe | Diff
--- A record containing values for all available options.
+-- | A record containing values for all available options.
data Options = Options { opt_help :: Bool,
opt_input :: IO String }
--- This constructs an instance of Options, with each of its members
--- set to default values.
+-- | This constructs an instance of Options, with each of its members
+-- set to default values.
default_options :: Options
default_options = Options { opt_help = False,
opt_input = getContents }
--- The options list that we construct associates a function with each
--- option. This function is responsible for updating an Options record
--- with the appropriate value.
+-- | The options list that we construct associates a function with
+-- each option. This function is responsible for updating an Options
+-- record with the appropriate value.
--
--- For more information and an example of this idiom, see,
+-- For more information and an example of this idiom, see,
--
--- http://www.haskell.org/haskellwiki/High-level_option_handling_with_GetOpt
+-- http://www.haskell.org/haskellwiki/High-level_option_handling_with_GetOpt
--
options :: [OptDescr (Options -> IO Options)]
options =
- [ Option ['h'][] (NoArg set_help) "Prints this help message.",
- Option ['i'][] (ReqArg set_input "FILE") "Read FILE instead of stdin." ]
+ [ Option "h" ["help"] (NoArg set_help) "Prints this help message.",
+ Option "i" ["input"] (ReqArg set_input "FILE") "Read FILE instead of stdin." ]
--- Takes an Options as an argument, and sets its opt_help member to
--- True.
+-- | Takes an Options as an argument, and sets its opt_help member to
+-- True.
set_help :: Options -> IO Options
-set_help opts = do
+set_help opts =
return opts { opt_help = True }
--- If the input file option is set, this function will update the
--- passed Options record with a new function for opt_input. The
--- default opt_input is to read from stdin, but if this option is set,
--- we replace that with readFile.
+-- | If the input file option is set, this function will update the
+-- passed Options record with a new function for opt_input. The
+-- default opt_input is to read from stdin, but if this option is
+-- set, we replace that with readFile.
set_input :: String -> Options -> IO Options
-set_input arg opts = do
+set_input arg opts =
return opts { opt_input = readFile arg }
--- The usage header
+-- | The usage header.
usage :: String
-usage = "Usage: hath [regexed|reduced|duplicated] [-h] [-i FILE]"
+usage = "Usage: hath [regexed|reduced|duped|diffed] [-h] [-i FILE] <input>"
--- The usage header, and all available flags (as generated by GetOpt)
+-- | The usage header, and all available flags (as generated by GetOpt).
help_text :: String
help_text = usageInfo usage options
--- Return a list of options.
+-- | Return a list of options.
parse_options :: IO Options
parse_options = do
argv <- getArgs
-- list, one after another, on a default_options record. The end
-- result should be an Options instance with all of its members set
-- correctly.
- opts <- foldl (>>=) (return default_options) actions
+ foldl (>>=) (return default_options) actions
- return opts
--- Return the mode if one was given.
+-- | Return the mode if one was given.
parse_mode :: IO Mode
parse_mode = do
argv <- getArgs
let (_, non_options, _) = getOpt Permute options argv
- if (null non_options)
- then do
- -- Default
- return Regex
- else do
- -- Some non-option was given, but were any of them modes?
- case (lowercase (non_options !! 0)) of
- "regex" -> return Regex
- "regexed" -> return Regex
- "reduce" -> return Reduce
- "reduced" -> return Reduce
- "dupe" -> return Dupe
- "duplicated" -> return Dupe
+ case non_options of
+ -- Default
+ [] -> return Regex
+ -- Some non-option was given, but were any of them modes?
+ (x:_) ->
+ case (lowercase x) of
+ "regex" -> return Regex
+ "regexed" -> return Regex
+ "reduce" -> return Reduce
+ "reduced" -> return Reduce
+ "dupe" -> return Dupe
+ "duped" -> return Dupe
+ "diff" -> return Diff
+ "diffed" -> return Diff
_ -> return Regex
--- Return a list of errors.
+-- | Return a list of errors.
parse_errors :: IO [String]
parse_errors = do
argv <- getArgs
--- Is the help option set?
+-- | Is the help option set?
help_set :: IO Bool
help_set = do
opts <- parse_options
return (opt_help opts)
--- Return our input function, getContents by default, or readFile if
--- the input file option was set.
+-- | Return our input function, getContents by default, or readFile if
+-- the input file option was set.
input_function :: IO (IO String)
input_function = do
opts <- parse_options