Merge remote-tracking branch 'idontgetoutmuch/ghc-head' into ghc-head

3 files changed, 27 insertions, 1 deletions

diff --git a/haddock-library/src/Documentation/Haddock/Parser.hs b/haddock-library/src/Documentation/Haddock/Parser.hs
index ca9e9d8d..123f5612 100644
--- a/haddock-library/src/Documentation/Haddock/Parser.hs
+++ b/haddock-library/src/Documentation/Haddock/Parser.hs
@@ -73,6 +73,8 @@ overIdentifier f d = g d
     g (DocCodeBlock x) = DocCodeBlock $ g x
     g (DocHyperlink x) = DocHyperlink x
     g (DocPic x) = DocPic x
+    g (DocMathInline x) = DocMathInline x
+    g (DocMathDisplay x) = DocMathDisplay x
     g (DocAName x) = DocAName x
     g (DocProperty x) = DocProperty x
     g (DocExamples x) = DocExamples x
@@ -113,7 +115,9 @@ parseStringBS = snd . parse p
   where
     p :: Parser (DocH mod Identifier)
     p = docConcat <$> many (monospace <|> anchor <|> identifier <|> moduleName
-                            <|> picture <|> markdownImage <|> hyperlink <|> bold
+                            <|> picture <|> mathDisplay <|> mathInline
+                            <|> markdownImage
+                            <|> hyperlink <|> bold
                             <|> emphasis <|> encodedChar <|> string'
                             <|> skipSpecialChar)
 
@@ -224,6 +228,22 @@ picture :: Parser (DocH mod a)
 picture = DocPic . makeLabeled Picture . decodeUtf8
           <$> disallowNewline ("<<" *> takeUntil ">>")
 
+-- | Inline math parser, surrounded by \\( and \\).
+--
+-- >>> parseString "\\(\\int_{-\\infty}^{\\infty} e^{-x^2/2} = \\sqrt{2\\pi}\\)"
+-- DocMathInline "\\int_{-\\infty}^{\\infty} e^{-x^2/2} = \\sqrt{2\\pi}"
+mathInline :: Parser (DocH mod a)
+mathInline = DocMathInline . decodeUtf8
+             <$> disallowNewline  ("\\(" *> takeUntil "\\)")
+
+-- | Display math parser, surrounded by \\[ and \\].
+--
+-- >>> parseString "\\[\\int_{-\\infty}^{\\infty} e^{-x^2/2} = \\sqrt{2\\pi}\\]"
+-- DocMathDisplay "\\int_{-\\infty}^{\\infty} e^{-x^2/2} = \\sqrt{2\\pi}"
+mathDisplay :: Parser (DocH mod a)
+mathDisplay = DocMathDisplay . decodeUtf8
+              <$> ("\\[" *> takeUntil "\\]")
+
 markdownImage :: Parser (DocH mod a)
 markdownImage = fromHyperlink <$> ("!" *> linkParser)
   where
diff --git a/haddock-library/src/Documentation/Haddock/Types.hs b/haddock-library/src/Documentation/Haddock/Types.hs
index 4ef89658..4d5bb68a 100644
--- a/haddock-library/src/Documentation/Haddock/Types.hs
+++ b/haddock-library/src/Documentation/Haddock/Types.hs
@@ -71,6 +71,8 @@ data DocH mod id
   | DocCodeBlock (DocH mod id)
   | DocHyperlink Hyperlink
   | DocPic Picture
+  | DocMathInline String
+  | DocMathDisplay String
   | DocAName String
   | DocProperty String
   | DocExamples [Example]
diff --git a/haddock-library/test/Documentation/Haddock/ParserSpec.hs b/haddock-library/test/Documentation/Haddock/ParserSpec.hs
index 2ef414fb..1169eb49 100644
--- a/haddock-library/test/Documentation/Haddock/ParserSpec.hs
+++ b/haddock-library/test/Documentation/Haddock/ParserSpec.hs
@@ -208,6 +208,10 @@ spec = do
       it "supports title for deprecated picture syntax" $ do
         "<<b a z>>" `shouldParseTo` image "b" "a z"
 
+    context "when parsing display math" $ do
+
+      it "accepts markdown syntax for display math containing newlines" $ do
+         "\\[\\pi\n\\pi\\]" `shouldParseTo` DocMathDisplay "\\pi\n\\pi"
 
     context "when parsing anchors" $ do
       it "parses a single word anchor" $ do