From 2189a6c28a72cf615b7febbe056f5227735813cd Mon Sep 17 00:00:00 2001
From: Neil Brown <neil@twistedsquare.com>
Date: Fri, 21 Mar 2008 20:03:47 +0000
Subject: [PATCH] Added support for list literals to the Rain parser

---
 common/TestUtils.hs        |  4 ++++
 frontends/ParseRain.hs     | 21 +++++++++++++++++++++
 frontends/ParseRainTest.hs | 17 +++++++++++++++++
 testcases/lists.rain       |  2 ++
 4 files changed, 44 insertions(+)

diff --git a/common/TestUtils.hs b/common/TestUtils.hs
index 42e416d..e8c08cb 100644
--- a/common/TestUtils.hs
+++ b/common/TestUtils.hs
@@ -52,6 +52,7 @@ import Metadata (emptyMeta)
 import Pass
 import Pattern
 import PrettyShow
+import TagAST
 import TestFramework
 import TreeUtils
 import Types
@@ -257,6 +258,9 @@ makeLiteralStringRainPattern = (stopCaringPattern emptyMeta) . mkPattern . makeL
 makeLiteralCharPattern :: Char -> Pattern
 makeLiteralCharPattern c = tag3 A.Literal DontCare A.Byte (tag2 A.ByteLiteral DontCare [c])
 
+makeListLiteralPattern :: [Pattern] -> Pattern
+makeListLiteralPattern items = mLiteral (A.List A.Any) (mListLiteral items)
+
 data ExprHelper = 
   Dy ExprHelper A.DyadicOp ExprHelper
   | Mon A.MonadicOp ExprHelper
diff --git a/frontends/ParseRain.hs b/frontends/ParseRain.hs
index 2defbbf..b99a888 100644
--- a/frontends/ParseRain.hs
+++ b/frontends/ParseRain.hs
@@ -204,12 +204,33 @@ integer
 integerLiteral :: RainParser A.Expression
 integerLiteral = do {i <- integer ; return $ A.Literal (findMeta i) A.Int i}
 
+listLiteral :: RainParser A.Expression
+listLiteral
+  = try $ do m <- sLeftQ
+             (do try sRightQ
+                 return $ A.Literal m (A.List A.Any) $ A.ListLiteral m []
+              <|> do e0 <- try expression
+                     (do try sRightQ
+                         return $ A.Literal m (A.List A.Any) $
+                           A.ListLiteral m [e0]
+                      -- Up until the first comma, this may be a type declaration
+                      -- in a cast expression, so we "try" all the way
+                      -- up until that comma
+                      <|> do try sComma
+                             es <- sepBy1 expression sComma
+                             sRightQ
+                             return $ A.Literal m (A.List A.Any) $
+                               A.ListLiteral m (e0 : es)
+                      )
+              )
+
 literal :: RainParser A.Expression
 literal = do {lr <- stringLiteral ; return $ A.Literal (findMeta lr) (A.List A.Byte) lr }
           <|> do {c <- literalCharacter ; return $ A.Literal (findMeta c) A.Byte c}
           <|> integerLiteral
           <|> do {m <- reserved "true" ; return $ A.True m}
           <|> do {m <- reserved "false" ; return $ A.False m}
+          <|> listLiteral
           <?> "literal"
 
 range :: RainParser A.Expression
diff --git a/frontends/ParseRainTest.hs b/frontends/ParseRainTest.hs
index e140da3..17ea95a 100644
--- a/frontends/ParseRainTest.hs
+++ b/frontends/ParseRainTest.hs
@@ -249,6 +249,23 @@ testLiteral =
   ,fail ("'\\",RP.literal)
   ,fail ("'ab'",RP.literal)  
   ,fail ("'\\n\\n'",RP.literal)  
+
+  -- Lists:
+  ,pass ("[0]", RP.literal, assertPatternMatch "testLiteral 400" $
+    makeListLiteralPattern [intLiteralPattern 0])
+  ,pass ("[]", RP.literal, assertPatternMatch "testLiteral 401" $
+    makeListLiteralPattern [])
+  ,pass ("[0,1,2]", RP.literal, assertPatternMatch "testLiteral 400" $
+    makeListLiteralPattern $ map intLiteralPattern [0,1,2])
+  ,pass ("['0']", RP.literal, assertPatternMatch "testLiteral 400" $
+    makeListLiteralPattern [makeLiteralCharPattern '0'])
+
+  ,fail ("[", RP.literal)
+  ,fail ("]", RP.literal)
+  ,fail ("[,]", RP.literal)
+  ,fail ("[0,]", RP.literal)
+  ,fail ("[,0]", RP.literal)
+  ,fail ("[0,,1]", RP.literal)
  ]
 
 testRange :: [ParseTest A.Expression]
diff --git a/testcases/lists.rain b/testcases/lists.rain
index e56540a..68367d9 100644
--- a/testcases/lists.rain
+++ b/testcases/lists.rain
@@ -5,6 +5,8 @@ process main (?uint8: in, !uint8: out, !uint8: err)
         alphabet = ['a' .. 'z'];
 
         alphabet += ['A' .. 'Z'];
+        
+        alphabet += ['0','1','2'] + ['3','4','5'] + "6789";
 
 	seqeach (c : alphabet)
 	{