add support for a bunch of keyword binary operators

Language/SQL/SimpleSQL/Parser.lhs

@@ -227,7 +227,18 @@ to be.
 >                    ,"||"]
 
 > binOpKeywordNames :: [String]
-> binOpKeywordNames = ["and", "or", "like"]
+> binOpKeywordNames = ["and", "or", "like"
+>                     ,"overlaps"]
+
+> binOpMultiKeywordNames :: [[String]]
+> binOpMultiKeywordNames = map words
+>     ["not like"
+>     ,"not similar"
+>     ,"is similar to"
+>     ,"is not similar to"
+>     ,"is distinct from"
+>     ,"is not distinct from"]
+
 
 used for between parsing
 
@@ -296,11 +307,16 @@ postgresql handles this
 >                 ,betweenSuffix e0
 >                 ,postfixOp e0
 >                 ] >>= trysuffix
->     opSymbol = choice (map (try . symbol) binOpSymbolNames
+>     opSymbol = choice
->                       ++ map (try . keyword)
+>         (map (try . symbol) binOpSymbolNames
->                          (if bExpr
+>         ++ map (try . keywords) binOpMultiKeywordNames
->                           then binOpKeywordNamesNoAnd
+>         ++ map (try . keyword)
->                           else binOpKeywordNames))
+>                (if bExpr
+>                 then binOpKeywordNamesNoAnd
+>                 else binOpKeywordNames))
+>     keywords ks = intercalate " " <$> keywords' ks
+>     keywords' [] = return []
+>     keywords' (k:ks) = (:) <$> keyword k <*> keywords' ks
 
 > sparens :: P ScalarExpr
 > sparens = Parens <$> parens scalarExpr'

Tests.lhs

@@ -161,13 +161,13 @@
 >     ,("a is not false", PostfixOp "is not false" (Iden "a"))
 >     ,("a is unknown", PostfixOp "is unknown" (Iden "a"))
 >     ,("a is not unknown", PostfixOp "is not unknown" (Iden "a"))
->     --,("a is distinct from b", Op "not" [])
+>     ,("a is distinct from b", BinOp "is distinct from" (Iden "a") (Iden "b"))
->     --,("a is not distinct from b", Op "not" [])
+>     ,("a is not distinct from b", BinOp "is not distinct from" (Iden "a") (Iden "b"))
->     --,("a like b", Op "not" [])
+>     ,("a like b", BinOp "like" (Iden "a") (Iden "b"))
->     --,("a not like b", Op "not" [])
+>     ,("a not like b", BinOp "not like" (Iden "a") (Iden "b"))
->     --,("a is similar to b", Op "not" [])
+>     ,("a is similar to b", BinOp "is similar to" (Iden "a") (Iden "b"))
->     --,("a is not similar to b", Op "not" [])
+>     ,("a is not similar to b", BinOp "is not similar to" (Iden "a") (Iden "b"))
->     --,("a overlaps b", Op "not" [])
+>     ,("a overlaps b", BinOp "overlaps" (Iden "a") (Iden "b"))
 >     --,("extract(day from t)", Op "not" [])
 >     ]