work on array constructors and expressions

Language/SQL/SimpleSQL/Parser.lhs

@@ -462,6 +462,17 @@ a match (select a from t)
 >     return $ \v -> Match v u q
 
 
+> arrayPostfix :: Parser (ValueExpr -> ValueExpr)
+> arrayPostfix = do
+>     es <- brackets (commaSep valueExpr)
+>     return $ \v -> Array v es
+
+> arrayCtor :: Parser ValueExpr
+> arrayCtor = keyword_ "array" >>
+>     choice
+>     [ArrayCtor <$> parens queryExpr
+>     ,Array (Iden (Name "array")) <$> brackets (commaSep valueExpr)]
+
 typename: used in casts. Special cases for the multi keyword typenames
 that SQL supports.
 
@@ -529,6 +540,7 @@ TODO: carefully review the precedences and associativities.
 >          [E.Postfix $ try quantifiedComparison
 >          ,E.Postfix matchPredicate]
 >         ,[binarySym "." E.AssocLeft]
+>         ,[postfix' arrayPostfix]
 >         ,[prefixSym "+", prefixSym "-"]
 >         ,[binarySym "^" E.AssocLeft]
 >         ,[binarySym "*" E.AssocLeft
@@ -618,6 +630,7 @@ fragile and could at least do with some heavy explanation.
 >               ,hostParameter
 >               ,caseValue
 >               ,cast
+>               ,arrayCtor
 >               ,specialOpKs
 >               ,parensTerm
 >               ,subquery
@@ -961,6 +974,13 @@ todo: work out the symbol parsing better
 > closeParen :: Parser Char
 > closeParen = lexeme $ char ')'
 
+> openBracket :: Parser Char
+> openBracket = lexeme $ char '['
+
+> closeBracket :: Parser Char
+> closeBracket = lexeme $ char ']'
+
+
 > comma :: Parser Char
 > comma = lexeme $ char ','
 
@@ -1005,6 +1025,9 @@ todo: work out the symbol parsing better
 > parens :: Parser a -> Parser a
 > parens = between openParen closeParen
 
+> brackets :: Parser a -> Parser a
+> brackets = between openBracket closeBracket
+
 > commaSep :: Parser a -> Parser [a]
 > commaSep = (`sepBy` comma)
 

Language/SQL/SimpleSQL/Pretty.lhs

@@ -14,7 +14,7 @@ which have been changed to try to improve the layout of the output.
 > import Language.SQL.SimpleSQL.Syntax
 > import Text.PrettyPrint (render, vcat, text, (<>), (<+>), empty, parens,
 >                          nest, Doc, punctuate, comma, sep, quotes,
->                          doubleQuotes)
+>                          doubleQuotes, brackets)
 > import Data.Maybe (maybeToList, catMaybes)
 
 > -- | Convert a query expr ast to concrete syntax.
@@ -162,7 +162,6 @@ which have been changed to try to improve the layout of the output.
 >     <+> (if u then text "unique" else empty)
 >     <+> parens (queryExpr sq)
 
-
 > valueExpr (In b se x) =
 >     valueExpr se <+>
 >     (if b then empty else text "not")
@@ -172,6 +171,13 @@ which have been changed to try to improve the layout of the output.
 >                      InList es -> commaSep $ map valueExpr es
 >                      InQueryExpr qe -> queryExpr qe)
 
+> valueExpr (Array v es) =
+>     valueExpr v <> brackets (commaSep $ map valueExpr es)
+
+> valueExpr (ArrayCtor q) =
+>     text "array" <> parens (queryExpr q)
+
+
 > unname :: Name -> String
 > unname (QName n) = "\"" ++ n ++ "\""
 > unname (Name n) = n

Language/SQL/SimpleSQL/Syntax.lhs

@@ -134,6 +134,12 @@
 >             QueryExpr
 >       | Match ValueExpr Bool -- true if unique
 >           QueryExpr
+>     | Array ValueExpr [ValueExpr] -- ^ represents an array
+>                                   -- access expression, or an array ctor
+>                                   -- e.g. a[3]. The first
+>                                   -- valueExpr is the array, the
+>                                   -- second is the subscripts/ctor args
+>     | ArrayCtor QueryExpr -- ^ this is used for the query expression version of array constructors, e.g. array(select * from t)>       deriving (Eq,Show,Read,Data,Typeable)
 >       deriving (Eq,Show,Read,Data,Typeable)
 
 > -- | Represents an identifier name, which can be quoted or unquoted.
@@ -154,7 +160,7 @@
 >                  | InQueryExpr QueryExpr
 >                    deriving (Eq,Show,Read,Data,Typeable)
 
-not sure if scalar subquery and aexists and unique should be represented like this
+not sure if scalar subquery, exists and unique should be represented like this
 
 > -- | A subquery in a value expression.
 > data SubQueryExprType