{--------------------------------------------------------------
-
- A main program to test the XQuery processor
- Programmer: Leonidas Fegaras (fegaras@cse.uta.edu)
- Date: 03/30/2008
-
---------------------------------------------------------------}

{-# OPTIONS_GHC -fth #-}

module Main where

import XML.HXQ.XQuery


f(d,s) = $(xe "<student dept='{$d/text()}'>{$s//firstname/text(),$s//lastname/text()}</student>")

main = do a <- $(xq ("  for $s in doc('data/cs.xml')//gradstudent          "
                ++"     order by $s/gpa descending, $s//lastname           "
                ++"     return <student>{$s//firstname/text(),             "
                ++"                      $s//lastname/text(),              "
                ++"                      $s/gpa/text()}</student>          "))
          putXSeq a
          let query name = $(xq " doc('data/cs.xml')//gradstudent[.//lastname = $name]//firstname ")
          b <- query $(xe " 'Galanis' ")
          putXSeq b
          c <- $(xq ("  <good-students>{                                   "
                  ++"       let $d := doc('data/cs.xml')                   "
                  ++"       for $s in $d//gradstudent                      "
                  ++"       where $s/gpa = 4.0                             "
                  ++"       return f($d//deptname,$s)                      "
                  ++"   }</good-students>                                  "))
          putXSeq c
          d <- $(xq ("    let $d := doc('data/cs.xml')//gradstudent  "
                   ++"    return ($d/../deptname,count($d))          "))
          putXSeq d
          putStrLn "Type an XQuery:"
          iquery <- getLine        -- read an XQuery from input
          e <- xquery iquery       -- evaluate it using the XQuery interpreter
          putXSeq e