{--------------------------------------------------------------
-
- The main program of the XQuery processor
- Programmer: Leonidas Fegaras (fegaras@cse.uta.edu)
- Date: 03/19/2008
-
---------------------------------------------------------------}

{-# OPTIONS_GHC -fth #-}

module Main where

import 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>          "))
          putStrLn (show a)
          let query name = $(xq " doc('data/cs.xml')//gradstudent[.//lastname = $name]//firstname ")
          b <- query $(xe " 'Galanis' ")      -- or use: query [XText "Galanis"]
          putStrLn (show 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>                                  "))
          putStrLn (show c)
          let q file = $(xq ("  let $d := doc($file)//gradstudent          "
                  ++"           return ($d/../deptname,count($d))          "))
          d <- q $(xe "'data/cs.xml'")
          putStrLn (show d)
          putStrLn "Type an XQuery:"
          iquery <- getLine
          e <- xquery iquery       -- Use the XQuery interpreter
          putStrLn (show e)