Add some parsing stuff to finished/ for Tag

finished/src/Data/Article.elm

@@ -3,15 +3,12 @@ module Data.Article
         ( Article
         , Body
         , Slug
-        , Tag
         , bodyToHtml
         , bodyToMarkdownString
         , decoder
         , decoderWithBody
         , slugParser
         , slugToString
-        , tagDecoder
-        , tagToString
         )
 
 import Data.Article.Author as Author exposing (Author)
@@ -110,24 +107,6 @@ slugToString (Slug slug) =
 
 
 
--- TAGS --
-
-
-type Tag
-    = Tag String
-
-
-tagToString : Tag -> String
-tagToString (Tag slug) =
-    slug
-
-
-tagDecoder : Decoder Tag
-tagDecoder =
-    Decode.map Tag Decode.string
-
-
-
 -- BODY --
 
 

finished/src/Data/Article/Tag.elm

@@ -0,0 +1,55 @@
+module Data.Article.Tag
+    exposing
+        ( Tag
+        , decoder
+        , encode
+        , listParser
+        , toString
+        )
+
+import Json.Decode as Decode exposing (Decoder)
+import Json.Encode as Encode exposing (Value)
+import Parser exposing ((|.), (|=), Parser, end, ignore, keep, oneOrMore, repeat, zeroOrMore)
+
+
+type Tag
+    = Tag String
+
+
+toString : Tag -> String
+toString (Tag str) =
+    str
+
+
+encode : Tag -> Value
+encode (Tag str) =
+    Encode.string str
+
+
+decoder : Decoder Tag
+decoder =
+    Decode.map Tag Decode.string
+
+
+listParser : Parser (List Tag)
+listParser =
+    Parser.succeed (List.map Tag)
+        |. ignore zeroOrMore isWhitespace
+        |= repeat zeroOrMore tag
+        |. end
+
+
+
+-- INTERNAL --
+
+
+tag : Parser String
+tag =
+    keep oneOrMore (\char -> not (isWhitespace char))
+        |. ignore zeroOrMore isWhitespace
+
+
+isWhitespace : Char -> Bool
+isWhitespace char =
+    -- Treat hashtags and commas as effectively whitespace; ignore them.
+    char == '#' || char == ',' || char == ' '