starlitcanopy/simple-sql-parser
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add haddock, reorder the fields in binop and jointref to be more natural

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This commit is contained in:
Jake Wheat 2013-12-14 13:33:15 +02:00
parent 65610af74e
commit c28db4d470
6 changed files with 107 additions and 77 deletions
Language/SQL/SimpleSQL
Pretty.lhs

18
Language/SQL/SimpleSQL/Pretty.lhs
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@ -2,6 +2,7 @@
This is the pretty printer code which takes AST values and turns them
back into SQL source text. It attempts to format the output nicely.
> -- | These is the pretty printing functions, which produce SQL source from ASTs. The code attempts to format the output in a readable way.
> module Language.SQL.SimpleSQL.Pretty
> (prettyQueryExpr
> ,prettyScalarExpr
@ -12,14 +13,17 @@ back into SQL source text. It attempts to format the output nicely.
> import Text.PrettyPrint
> import Data.Maybe
> -- | Convert a query expr ast to concrete syntax.
> prettyQueryExpr :: QueryExpr -> String
> prettyQueryExpr = render . queryExpr
> -- | Convert a scalar expr ast to concrete syntax.
> prettyScalarExpr :: ScalarExpr -> String
> prettyScalarExpr = render . scalarExpr
> -- | Convert a list of query exprs to concrete syntax. A semi colon is inserted following each query expr.
> prettyQueryExprs :: [QueryExpr] -> String
> prettyQueryExprs = render . vcat . map ((<> text ";") . queryExpr)
> prettyQueryExprs = render . vcat . map ((<> text ";\n") . queryExpr)
= scalar expressions
@ -75,9 +79,9 @@ back into SQL source text. It attempts to format the output nicely.
> scalarExpr (PrefixOp f e) = text f <+> scalarExpr e
> scalarExpr (PostfixOp f e) = scalarExpr e <+> text f
> scalarExpr (BinOp "and" e0 e1) =
> scalarExpr (BinOp e0 "and" e1) =
> sep [scalarExpr e0, text "and" <+> scalarExpr e1]
> scalarExpr (BinOp f e0 e1) =
> scalarExpr (BinOp e0 f e1) =
> scalarExpr e0 <+> text f <+> scalarExpr e1
> scalarExpr (Case t ws els) =
@ -171,7 +175,7 @@ back into SQL source text. It attempts to format the output nicely.
> <+> maybe empty (parens . commaSep . map text) cs
> tr (JoinParens t) = parens $ tr t
> tr (JoinQueryExpr q) = parens $ queryExpr q
> tr (JoinTableRef jt t0 t1 jc) =
> tr (JoinTableRef t0 jt t1 jc) =
> sep [tr t0
> ,joinText jt jc
> ,tr t1
@ -181,11 +185,11 @@ back into SQL source text. It attempts to format the output nicely.
> Just JoinNatural -> text "natural"
> _ -> empty
> ,case jt of
> Inner -> text "inner"
> JInner -> text "inner"
> JLeft -> text "left"
> JRight -> text "right"
> Full -> text "full"
> Cross -> text "cross"
> JFull -> text "full"
> JCross -> text "cross"
> ,text "join"]
> joinCond (Just (JoinOn e)) = text "on" <+> scalarExpr e
> joinCond (Just (JoinUsing es)) = text "using" <+> parens (commaSep $ map text es)