From 0025e078eafa05f82b40b43f78df653747eebee8 Mon Sep 17 00:00:00 2001
From: aarne <aarne@chalmers.se>
Date: Sun, 19 Oct 2014 17:43:39 +0000
Subject: [PATCH] (un)lexmixed: added the other math environments than $ used
 in latex

---
 src/compiler/GF/Command/Commands.hs |  4 ++--
 src/runtime/haskell/PGF/Lexing.hs   | 14 +++++++-------
 2 files changed, 9 insertions(+), 9 deletions(-)

diff --git a/src/compiler/GF/Command/Commands.hs b/src/compiler/GF/Command/Commands.hs
index e67de95cf..348a942d8 100644
--- a/src/compiler/GF/Command/Commands.hs
+++ b/src/compiler/GF/Command/Commands.hs
@@ -1367,13 +1367,13 @@ stringOpOptions = sort $ [
        ("from_utf8","decode from utf8 (default)"),
        ("lextext","text-like lexer"),
        ("lexcode","code-like lexer"),
-       ("lexmixed","mixture of text and code (code between $...$)"),
+       ("lexmixed","mixture of text and code, as in LaTeX (code between $...$, \\(...)\\, \\[...\\])"),
        ("to_cp1251","encode to cp1251 (Cyrillic used in Bulgarian resource)"),
        ("to_html","wrap in a html file with linebreaks"),
        ("to_utf8","encode to utf8 (default)"),
        ("unlextext","text-like unlexer"),
        ("unlexcode","code-like unlexer"),
-       ("unlexmixed","mixture of text and code (code between $...$)"),
+       ("unlexmixed","mixture of text and code (code between $...$, \\(...)\\, \\[...\\])"),
        ("unchars","unlexer that puts no spaces between tokens"),
        ("unwords","unlexer that puts a single space between tokens (default)"),
        ("words","lexer that assumes tokens separated by spaces (default)")
diff --git a/src/runtime/haskell/PGF/Lexing.hs b/src/runtime/haskell/PGF/Lexing.hs
index dde39b494..5d7acb398 100644
--- a/src/runtime/haskell/PGF/Lexing.hs
+++ b/src/runtime/haskell/PGF/Lexing.hs
@@ -67,18 +67,18 @@ lexLatexCode = restoreBackslash . lexCode where --- quick hack: postprocess Hask
 
 -- | LaTeX style lexer, with "math" environment using Code between $...$
 lexMixed :: String -> [String]
-lexMixed = concat . alternate False where
-  alternate env s = case s of
-    _:_ -> case break (=='$') s of
-      (t,[])  -> lex env t : []
-      (t,c:m) -> lex env t : [[c]] : alternate (not env) m
-    _ -> []
+lexMixed = concat . alternate False [] where
+  alternate env t s = case s of
+    '$':cs -> lex env (reverse t) : ["$"] : alternate (not env) [] cs
+    '\\':c:cs | elem c "()[]" -> lex env (reverse t) : [['\\',c]] : alternate (not env) [] cs
+    c:cs -> alternate env (c:t) cs
+    _ -> [lex env (reverse t)]
   lex env = if env then lexLatexCode else lexText
 
 unlexMixed :: [String] -> String
 unlexMixed = capitInit . concat . alternate False where
   alternate env s = case s of
-    _:_ -> case break (=="$") s of
+    _:_ -> case break (flip elem ["$","\\[","\\]","\\(","\\)"]) s of
       (t,[])  -> unlex env t : []
       (t,c:m) -> unlex env t : sep env c m : alternate (not env) m
     _ -> []