+ Changed 'escapedChar' in Markdown reader so that only the

  characters Markdown escapes are escaped in strict mode.
  When not in strict mode, Pandoc allows all non-alphanumeric 
  characters to be escaped.
+ Added documentation of backslash escapes to README.


git-svn-id: https://pandoc.googlecode.com/svn/trunk@461 788f1e2b-df1e-0410-8736-df70ead52e1b

2 files changed, 30 insertions, 1 deletions

diff --git a/README b/README
index f95a93758..23290fadd 100644
--- a/README
+++ b/README
@@ -342,6 +342,28 @@ using the `hsmarkdown` wrapper.
 [standard markdown]:  http://daringfireball.net/projects/markdown/syntax
   "Markdown syntax description"
 
+Backslash escapes
+-----------------
+
+Except inside a code block or inline code, any punctuation or space
+character preceded by a backslash will be treated literally, even if it
+would normally indicate formatting.  Thus, for example, if one writes
+
+    *\*hello\**
+
+one will get
+
+    <em>*hello*</em>
+
+instead of
+
+    <strong>hello</strong>
+
+This rule is easier to remember than standard markdown's rule,
+which allows only the following characters to be backslash-escaped:
+
+    \`*_{}[]()>#+-.!
+
 Lists
 -----
 
diff --git a/src/Text/Pandoc/Readers/Markdown.hs b/src/Text/Pandoc/Readers/Markdown.hs
index f72918a0e..4e6a7b39c 100644
--- a/src/Text/Pandoc/Readers/Markdown.hs
+++ b/src/Text/Pandoc/Readers/Markdown.hs
@@ -32,6 +32,7 @@ module Text.Pandoc.Readers.Markdown (
                                     ) where
 
 import Data.List ( findIndex, sortBy )
+import Data.Char ( isAlphaNum )
 import Text.ParserCombinators.Pandoc
 import Text.Pandoc.Definition
 import Text.Pandoc.Readers.LaTeX ( rawLaTeXInline, rawLaTeXEnvironment )
@@ -535,7 +536,13 @@ inline = choice [ rawLaTeXInline', escapedChar, special, text ] <?> "inline"
 special = choice [ noteRef, inlineNote, link, referenceLink, rawHtmlInline', 
                    autoLink, image ] <?> "link, inline html, note, or image"
 
-escapedChar = escaped anyChar
+escapedChar = try $ do
+  char '\\'
+  state <- getState
+  result <- if stateStrict state 
+              then oneOf "\\`*_{}[]()>#+-.!"
+              else satisfy (not . isAlphaNum)
+  return (Str [result])
 
 ltSign = try (do
   notFollowedBy (noneOf "<")   -- continue only if it's a <