From d4aa63730eba13677520a00d9d918966db30887d Mon Sep 17 00:00:00 2001
From: Philippe Pittoli <karchnu@karchnu.fr>
Date: Fri, 19 Jan 2024 02:27:11 +0100
Subject: [PATCH] More consistent function naming.

---
 makefile                            |  2 +-
 src/GenericParser.purs              |  4 +-
 src/GenericParser/DomainParser.purs | 67 ++++++++++++++++-------------
 src/GenericParser/Parser.purs       | 17 ++++----
 4 files changed, 47 insertions(+), 43 deletions(-)

diff --git a/makefile b/makefile
index da5de78..59d6916 100644
--- a/makefile
+++ b/makefile
@@ -6,5 +6,5 @@ build:
 run:
 	spago run
 
-test:
+t:
 	spago test
diff --git a/src/GenericParser.purs b/src/GenericParser.purs
index ee00eb4..e186ea3 100644
--- a/src/GenericParser.purs
+++ b/src/GenericParser.purs
@@ -3,5 +3,5 @@ module GenericParser
   , module GenericParser.DomainParser
   ) where
 
-import GenericParser.Parser (Position, PositionString, Input, Error, Value, Result, Parser(..), parse, current_position, failError, fail, success, item, sat, digit, lower, upper, letter, alphanum, char, string, ident, nat, int, space, token, identifier, natural, integer, symbol, many1)
-import GenericParser.DomainParser (Size, DomainError(..), let_dig, let_dig_hyp, ldh_str, label_maxsize, max_domain_length, last_char, parse_last_char, tryMaybe, try, label, subdomain, eof, sub_eof, domain)
+import GenericParser.Parser (Position, PositionString, Input, Error, Value, Result, Parser(..), parse, current_position, failureError, failure, success, item, sat, digit, lower, upper, letter, alphanum, char, string, ident, nat, int, space, token, identifier, natural, integer, symbol, many1)
+import GenericParser.DomainParser (Size, DomainError(..), let_dig, let_dig_hyp, ldh_str, max_label_length, max_domain_length, tryMaybe, try, label, subdomain, eof, sub_eof, domain)
diff --git a/src/GenericParser/DomainParser.purs b/src/GenericParser/DomainParser.purs
index cae437e..edbcaf3 100644
--- a/src/GenericParser/DomainParser.purs
+++ b/src/GenericParser/DomainParser.purs
@@ -3,17 +3,16 @@ module GenericParser.DomainParser where
 
 import Prelude (bind, not, pure, ($), (&&), (*>), (<<<), (<>), (>), (-))
 
+import Control.Alt ((<|>))
 import Control.Lazy (defer)
-import Data.Maybe (Maybe(..), maybe)
-import Data.Either (Either(..))
 import Data.Array as A
+import Data.Either (Either(..))
+import Data.Maybe (Maybe(..), maybe)
 import Data.String as S
 import Data.String.CodeUnits as CU
-import Control.Alt ((<|>))
--- import Control.Plus (empty)
 
 import GenericParser.Parser (Parser(..)
-                            , success, failError
+                            , success, failureError
                             , current_position
                             , alphanum, char, letter, many1, parse, string)
 
@@ -37,41 +36,35 @@ let_dig_hyp = let_dig <|> char '-'
 ldh_str :: forall e. Parser e (Array Char)
 ldh_str = many1 let_dig_hyp
 
--- TODO: 63
-label_maxsize :: Int
-label_maxsize = 7
+-- | WARNING: Verify the actual maximum length for a label.
+-- | Current maximum accepted length for a label is 63.
+max_label_length :: Int
+max_label_length = 63
 
--- TODO: 255?
+-- | WARNING: Verify the actual maximum length for a domain.
+-- | Current maximum accepted length for a domain is 255.
 max_domain_length :: Int
-max_domain_length = 15
-
-last_char :: String -> Maybe Char
-last_char = A.last <<< CU.toCharArray
-
-parse_last_char :: forall e. String -> Parser e Char -> Boolean
-parse_last_char s p = case last_char s of
-  Nothing -> false
-  Just c -> case parse p { string: CU.singleton c, position: 0 } of
-    Left _  -> false
-    _       -> true
+max_domain_length = 255
 
 -- | `tryMaybe` provides a way to accept a faulty parser and
 -- | just rewinds back to previous input state if an error occurs.
 tryMaybe :: forall e a. Parser e a -> Parser e (Maybe a)
 tryMaybe p = Parser p'
   where p' input = case parse p input of
-                   Left _                   -> Right { suffix: input, result: Nothing }
-                   Right { suffix, result } -> Right { suffix,        result: Just result }
+                   Left _                   -> success input Nothing
+                   Right { suffix, result } -> success suffix (Just result)
 
 -- | `try` provides a way to accept a faulty parser and
 -- | just rewinds back to previous input state if a non-specific error occurs.
+-- | The difference with `tryMaybe` is that `try` will forward the error if it is
+-- | a specific one, meanning that `error` isn't `Nothing`.
 try :: forall e a. Parser e a -> Parser e (Maybe a)
 try p = Parser p'
   where p' input = case parse p input of
+                   Right { suffix, result } -> success suffix (Just result)
                    Left { position, error } -> case error of
-                     Nothing -> Right { suffix: input, result: Nothing }
-                     _       -> Left { position, error }
-                   Right { suffix, result } -> Right { suffix, result: Just result }
+                     Nothing -> success input Nothing
+                     _       -> failureError position error
 
 -- | From RFC 1035: <label> ::= <letter> [ [ <ldh-str> ] <let-dig> ]
 label :: Parser DomainError String
@@ -79,16 +72,28 @@ label = do
   pos <- current_position
   maybel <- tryMaybe letter
   case maybel of
-    Nothing -> Parser \_ -> failError pos (Just InvalidCharacter)
+    Nothing -> Parser \_ -> failureError pos (Just InvalidCharacter)
     Just l -> do
       s <- tryMaybe ldh_str
       lastpos <- current_position
       let labelstr = CU.singleton l <> maybe "" CU.fromCharArray s
-      if (S.length labelstr > label_maxsize)
-      then Parser \_ -> failError pos (Just <<< SubdomainTooLarge $ S.length labelstr)
+      if (S.length labelstr > max_label_length)
+      then Parser \_ -> failureError pos (Just <<< SubdomainTooLarge $ S.length labelstr)
       else if (S.length labelstr > 1 && not (parse_last_char labelstr let_dig))
-           then Parser \_ -> failError (lastpos - 1) (Just InvalidCharacter)
+           then Parser \_ -> failureError (lastpos - 1) (Just InvalidCharacter)
            else pure labelstr
+  where
+     -- Get the last character of a String.
+     last_char :: String -> Maybe Char
+     last_char = A.last <<< CU.toCharArray
+
+     -- Parse the last character of a String.
+     parse_last_char :: forall e. String -> Parser e Char -> Boolean
+     parse_last_char s p = case last_char s of
+       Nothing -> false
+       Just c -> case parse p { string: CU.singleton c, position: 0 } of
+         Left _  -> false
+         _       -> true
 
 -- | From RFC 1035: <subdomain> ::= <label> | <subdomain> "." <label>
 subdomain :: Parser DomainError String
@@ -108,7 +113,7 @@ subdomain = do
 eof :: Parser DomainError String
 eof = Parser \input -> case S.length input.string of
   0 -> success input ""
-  _ -> failError input.position (Just EOFExpected)
+  _ -> failureError input.position (Just EOFExpected)
 
 -- | Test for the domain to be a list of subdomains then an end-of-file.
 -- | Said otherwise, the input must only contain a domain (with or without a final dot '.').
@@ -120,7 +125,7 @@ sub_eof = do
   pos <- current_position
   let parsed_domain = did_we_parse_the_final_point maybe_final_point sub
   if S.length parsed_domain > max_domain_length
-  then Parser \_ -> failError pos (Just <<< DomainTooLarge $ S.length parsed_domain)
+  then Parser \_ -> failureError pos (Just <<< DomainTooLarge $ S.length parsed_domain)
   else pure parsed_domain
   where
     did_we_parse_the_final_point Nothing sub = sub
diff --git a/src/GenericParser/Parser.purs b/src/GenericParser/Parser.purs
index 2712add..33c9fe7 100644
--- a/src/GenericParser/Parser.purs
+++ b/src/GenericParser/Parser.purs
@@ -5,10 +5,9 @@ import Control.Alt (class Alt, (<|>))
 import Control.Alternative (class Alternative)
 import Control.Lazy (class Lazy)
 import Control.Plus (class Plus, empty)
-
 import Data.Array as A
-import Data.Int as Int
 import Data.Either (Either(..))
+import Data.Int as Int
 import Data.Maybe (Maybe(..))
 import Data.String.CodeUnits (toCharArray, fromCharArray)
 
@@ -32,16 +31,16 @@ current_position = Parser \input -> success input input.position
 
 -- | Fail with a specified error.
 -- | When a parsing has a specified error, no alternative will be tried and the error is reported.
-failError :: forall e v. Position -> Maybe e -> Result e v
-failError position error = Left { position, error }
+failureError :: forall e v. Position -> Maybe e -> Result e v
+failureError position error = Left { position, error }
 
 -- | Fail without a specified error.
 -- | This is used in generic parsers not attached to a specified context,
 -- | such as `digit` or `letter`.
 -- | Also, this can be used to express a possibly expected invalid parsing that should not
 -- | halt the parsing, but rather let an alternative path to be tried.
-fail :: forall e v. Position -> Result e v
-fail position = failError position Nothing
+failure :: forall e v. Position -> Result e v
+failure position = failureError position Nothing
 
 -- | `success` constructs a result value for a successful parsing.
 -- | It requires the input (a string with its current position) and the result.
@@ -53,7 +52,7 @@ item :: forall e. Parser e Char
 item = Parser p
   where
     p input = case A.uncons (toCharArray input.string) of
-      Nothing                    -> fail input.position
+      Nothing                    -> failure input.position
       Just { head: x, tail: xs } -> success { string: (fromCharArray xs), position: input.position+1 } x
 
 instance functorParser :: Functor (Parser e) where
@@ -87,12 +86,12 @@ instance altParser :: Alt (Parser e) where
       p stream = case p1 stream of
         Left { position, error } -> case error of
           Nothing -> p2 stream
-          _       -> failError position error
+          _       -> failureError position error
         Right right -> Right right
 
 instance plusParser :: Plus (Parser e) where
   empty :: forall v. Parser e v
-  empty = Parser \input -> fail input.position
+  empty = Parser \input -> failure input.position
 
 instance alternativeParser :: Alternative (Parser e)