HXQ-0.14.0: A Compiler from XQuery to Haskell Source code Contents Index

Text.XML.HXQ.XQuery

Contents The XML Data Representation The XQuery Compiler The XQuery Interpreter The XQuery Compiler with Database Connectivity The XQuery Interpreter with Database Connectivity Shredding and Publishing XML Documents Using a Relational Database Other Functions

Description

HXQ is a fast and space-efficient compiler from XQuery (the standard query language for XML) to embedded Haskell code. The translation is based on Haskell templates. It also provides an interpreter for evaluating ad-hoc XQueries read from input or from files and optional database connectivity using HDBC. For more information, look at http://lambda.uta.edu/HXQ/.

Synopsis

data XTree = XElem !Tag !AttList !Int XTree [XTree] | XText !String | XInt !Int | XFloat !Float | XBool !Bool | XPI Tag String | XGERef Tag | XComment String | XError String | XNull | XNoPad type XSeq = [XTree] type Tag = String type AttList = [(Name, String)] putXSeq :: XSeq -> IO () xq :: String -> Q Exp xe :: String -> Q Exp xquery :: String -> IO XSeq xqdb :: String -> Q Exp xqueryDB :: String -> Connection -> IO XSeq genSchema :: Connection -> String -> String -> IO Table shred :: Connection -> String -> String -> IO () shredC :: String -> String -> String -> Q Exp printSchema :: Connection -> String -> IO () createIndex :: Connection -> String -> String -> IO () data XMLEvent = StartEvent Name [(Name, String)] | EmptyEvent Name [(Name, String)] | EndEvent Name | TextEvent String | PIEvent Name String | GERefEvent Name | CommentEvent String | ErrorEvent String connect :: FilePath -> IO Connection disconnect :: Connection -> IO () commit :: Connection -> IO () rollback :: Connection -> IO () prepareSQL :: Connection -> String -> IO Statement executeSQL :: Statement -> XSeq -> IO XSeq qx

The XML Data Representation

data XTree Source

A rose tree representation of XML data. An XML element is: XElem tagname atributes preorder parent children. The preorder numbering is the document order of elements. The parent is a cyclic reference to the parent element. Constructors XElem !Tag !AttList !Int XTree [XTree] an XML tree node (element) XText !String an XML tree leaf (PCDATA) XInt !Int an XML tree leaf (int) XFloat !Float an XML tree leaf (float) XBool !Bool an XML tree leaf (boolean) XPI Tag String processing instruction XGERef Tag general entity reference XComment String comment XError String error report XNull null value XNoPad marker for no padding in XSeq Instances Eq XTree Show XTree

type XSeq = [XTree] Source

type Tag = String Source

type AttList = [(Name, String)] Source

putXSeq :: XSeq -> IO () Source

Print the XQuery result (which is a sequence of XML fragments) without buffering.

The XQuery Compiler

xq :: String -> Q Exp Source

Run an XQuery that may read XML documents. When evaluated, it returns IO XSeq.

xe :: String -> Q Exp Source

Run an XQuery expression that does not perform IO. When evaluated, it returns XSeq.

The XQuery Interpreter

xquery :: String -> IO XSeq Source

Evaluate the XQuery using the interpreter.

The XQuery Compiler with Database Connectivity

xqdb :: String -> Q Exp Source

Run an XQuery that reads XML documents and queries databases. When evaluated, it returns Connection -> IO XSeq.

The XQuery Interpreter with Database Connectivity

xqueryDB :: String -> Connection -> IO XSeq Source

Evaluate the XQuery with database connectivity using the interpreter.

Shredding and Publishing XML Documents Using a Relational Database

genSchema :: Connection -> String -> String -> IO Table Source

Create a schema for an XML document into the database under the given name.

shred :: Connection -> String -> String -> IO () Source

Store an XML document into the database under the given name.

shredC :: String -> String -> String -> Q Exp Source

Store an XML document into the database under the given name. Generates Haskell code.

printSchema :: Connection -> String -> IO () Source

Print the relational schema of the XML document stored in the database under the given name

createIndex :: Connection -> String -> String -> IO () Source

Create a secondary index on tagname for the shredded document under the given name..

Other Functions

data XMLEvent Source

Constructors StartEvent Name [(Name, String)] EmptyEvent Name [(Name, String)] EndEvent Name TextEvent String PIEvent Name String GERefEvent Name CommentEvent String ErrorEvent String Instances Read XMLEvent Show XMLEvent

connect :: FilePath -> IO Connection Source

Connect to the relational database in filepath

disconnect :: Connection -> IO () Source

Disconnect from the relational database

commit :: Connection -> IO () Source

commit the updates to the database

rollback :: Connection -> IO () Source

rollback the updates from the database

prepareSQL :: Connection -> String -> IO Statement Source

executeSQL :: Statement -> XSeq -> IO XSeq Source

qx

Produced by Haddock version 2.4.2