Experimental working commit, programm will compile

But the Proof that the domain of the local function
is not right. Also if in the definition of our local
function we just use f(x) = x then we get a technical
ambigus parse

1 files changed, 15 insertions, 2 deletions

diff --git a/source/Syntax/Token.hs b/source/Syntax/Token.hs
index cb3f4cb..52da86a 100644
--- a/source/Syntax/Token.hs
+++ b/source/Syntax/Token.hs
@@ -189,6 +189,7 @@ toks = whitespace *> goNormal id <* eof
                 Nothing -> pure (f [])
                 Just t@Located{unLocated = BeginEnv "math"} -> goMath (f . (t:))
                 Just t@Located{unLocated = BeginEnv "align*"} -> goMath (f . (t:))
+                Just t@Located{unLocated = BeginEnv "cases"} -> goMath (f . (t:))
                 Just t -> goNormal (f . (t:))
         goText f = do
             r <- optional textToken
@@ -204,6 +205,7 @@ toks = whitespace *> goNormal id <* eof
                 Nothing -> pure (f [])
                 Just t@Located{unLocated = EndEnv "math"} -> goNormal (f . (t:))
                 Just t@Located{unLocated = EndEnv "align*"} -> goNormal (f . (t:))
+                Just t@Located{unLocated = EndEnv "cases"} -> goNormal (f . (t:))
                 Just t@Located{unLocated = BeginEnv "text"} -> goText (f . (t:))
                 Just t@Located{unLocated = BeginEnv "explanation"} -> goText (f . (t:))
                 Just t -> goMath (f . (t:))
@@ -219,12 +221,12 @@ toks = whitespace *> goNormal id <* eof
 -- | Parses a single normal mode token.
 tok :: Lexer (Located Token)
 tok =
-    word <|> var <|> symbol <|> mathBegin <|> alignBegin <|> begin <|> end <|> opening <|> closing <|> label <|> ref <|> command
+    word <|> var <|> symbol <|> mathBegin <|> alignBegin <|> casesBegin <|> begin <|> end <|> opening <|> closing <|> label <|> ref <|> command
 
 -- | Parses a single math mode token.
 mathToken :: Lexer (Located Token)
 mathToken =
-    var <|> symbol <|> number <|> begin <|> alignEnd <|> end <|> opening <|> closing <|> beginText <|> beginExplanation <|> mathEnd <|> command
+    var <|> symbol <|> number <|> begin <|> alignEnd <|> casesEnd <|> end <|> opening <|> closing <|> beginText <|> beginExplanation <|> mathEnd <|> command
 
 beginText :: Lexer (Located Token)
 beginText = lexeme do
@@ -277,6 +279,11 @@ alignBegin = guardM isTextMode *> lexeme do
     setMathMode
     pure (BeginEnv "align*")
 
+casesBegin :: Lexer (Located Token)
+casesBegin = guardM isTextMode *> lexeme do
+    Char.string "\\begin{cases}"
+    setMathMode
+    pure (BeginEnv "cases")
 
 -- | Parses a single end math token.
 mathEnd :: Lexer (Located Token)
@@ -291,6 +298,12 @@ alignEnd = guardM isMathMode *> lexeme do
     setTextMode
     pure (EndEnv "align*")
 
+casesEnd :: Lexer (Located Token)
+casesEnd = guardM isMathMode *> lexeme do
+    Char.string "\\end{cases}"
+    setTextMode
+    pure (EndEnv "cases")
+
 
 -- | Parses a word. Words are returned casefolded, since we want to ignore their case later on.
 word :: Lexer (Located Token)