Question

I’m just learning scala and im trying to import an XML file to a Map. The XML holds definitions using <word></word> and <description></description>. When I attempt to create the map I get the error:

Value update is not member of scala.collection.immutable.Map[String, String]

Any pointers would be appreciated!

    package main
import scala.xml._

object main {

  def main(args: Array[String]): Unit = {
    val definitions = XML.load("src\\main\\Definitions.xml");
    val definitionMap = (Map[String, String]() /: (definitions \ "word")) { (map , defNode) =>
        val word = (defNode \ "word").text.toString()
        val description = (defNode \ "description").text.toString()
        map(word) = description
    }
    println(definitions.getClass())
    println("Number of elements is " + (definitions \\ "word").size)
  }

}

and the XML is formatted as such:

<?xml version="1.0"?>
<definitions>
    <entry>
        <word>Ontology</word>
        <description>A set of representational primitives with which to model a domain of knowledge or discourse.</description>
    </entry>

    <entry>
        <word>Diagnostic</word>
        <description>The process of locating problems with software, hardware, or any combination thereof in a system, or a network of systems.</description>
    </entry>
    <entry>
        <word>Malware</word>
        <description>Software that is intended to damage or disable computers and computer systems.</description>
    </entry>
    <entry>
        <word>Capacitor</word>
        <description>A device used to store an electric charge, consisting of one or more pairs of conductors separated by an insulator.</description>
    </entry>
    <entry>
        <word>Stress Test</word>
        <description>A test measuring how a system functions when subjected to controlled amounts of stress.</description>
    </entry>
    <entry>
        <word>Registry</word>
        <description>A hierarchical database that stores configuration settings and options on Microsoft Windows operating systems.</description>
    </entry>
    <entry>
        <word>Antivirus</word>
        <description>Designed to detect and remove computer viruses.</description>
    </entry>
</definitions>

Answer 1

You can’t change immutable data structures, that’s what compiler wants to say. Instead of updating,

map(word) = description

you should continuously add records to map.

map + (word -> description)