Rain: added parsing of simple ranges (such as [0..100])

LexRain.x

@@ -37,6 +37,7 @@ $hexDigit = [0-9 a-f A-F]
           | "+" | "-" | "*" | "/" | "%"
           | ">=" | "<="
           | "<" | ">"
+          | ".."
           | "process" | "pareach" | "seqeach" | "par" | "seq" 
           | "run"
           | "if" | "while" | "else"

RainParse.hs

@@ -66,6 +66,7 @@ sColon = reserved ":"
 sComma = reserved ","
 sIn = reserved "?"
 sOut = reserved "!"
+sDots = reserved ".."
 --}}}
 
 --{{{ Keywords
@@ -198,13 +199,19 @@ integer
     testToken (L.TokDecimalLiteral d) = Just d
     testToken _ = Nothing
 
+integerLiteral :: RainParser A.Expression
+integerLiteral = do {i <- integer ; return $ A.Literal (findMeta i) A.Int i}
+
 literal :: RainParser A.Expression
 literal = do {(lr, dim) <- stringLiteral ; return $ A.Literal (findMeta lr) (A.Array [dim] A.Byte) lr }
-          <|> do {i <- integer ; return $ A.Literal (findMeta i) A.Int i}
+          <|> integerLiteral
           <|> do {m <- reserved "true" ; return $ A.True m}
           <|> do {m <- reserved "false" ; return $ A.False m}
           <?> "literal"
 
+range :: RainParser A.Expression
+range = try $ do {m <- sLeftQ ; begin <- integerLiteral; sDots ; end <- integerLiteral ; sRightQ ; return $ A.ExprConstr m $ A.RangeConstr m begin end}
+
 expression :: RainParser A.Expression
 expression
   = try compExpression
@@ -231,6 +238,7 @@ expression
     subExpr' :: RainParser A.Expression
     subExpr' = do {id <- variableId ; return $ A.ExprVariable (findMeta id) id}
                <|> literal
+               <|> range
                <|> do {(m,op) <- monadicArithOp ; rhs <- subExpr' ; return $ A.Monadic m op rhs}
                <|> do {sLeftR ; e <- expression ; sRightR ; return e}
 

RainParseTest.hs

@@ -216,6 +216,16 @@ testLiteral =
   
  ]
 
+testRange :: [ParseTest A.Expression]
+testRange =
+ [
+  pass("[0..1]", RP.expression, assertPatternMatch "testRange 0" $ tag2 A.ExprConstr DontCare $ tag3 A.RangeConstr DontCare (intLiteralPattern 0) (intLiteralPattern 1))
+  ,pass("[0..10000]", RP.expression, assertPatternMatch "testRange 0" $ tag2 A.ExprConstr DontCare $ tag3 A.RangeConstr DontCare (intLiteralPattern 0) (intLiteralPattern 10000))
+  ,pass("[-3..-1]", RP.expression, assertPatternMatch "testRange 0" $ tag2 A.ExprConstr DontCare $ tag3 A.RangeConstr DontCare (intLiteralPattern $ -3) (intLiteralPattern $ -1))
+  --For now, at least, this should fail:
+  ,fail("[0..x]", RP.expression)
+ ]
+
 --Helper function for ifs:
 makeIf :: [(A.Expression,A.Process)] -> A.Process
 makeIf list = A.If m $ A.Several m (map makeChoice list)
@@ -518,6 +528,7 @@ tests = TestList
  [
   parseTests testExprs,
   parseTests testLiteral,
+  parseTests testRange,
   parseTests testWhile,
   parseTests testSeq,
   parseTests testPar,