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Example sms service in studybook is not compiling

iluah (5)
Hi all,

I just joined this website for a problem I can't seem to figure out. I am trying to compile a sms service that is used as an example in my studybook. It has one provider with a total of 10 mobile phone users that can send text messages to eachother.

The error is at:
Mobile *Provider :: getMobile ( int nr );

compiler error:
error: extra qualification 'Provider::' on member 'getMobile' [-fpermissive]|

Can someone explain this error and make the code compile?

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// Example 9.4 SMS, Provider, Mobile
#include <iostream>
#include <sstream>
#include <string>
using namespace std;

class SMS {
private:
  int from, to;   // phone numbers sending
  string text;
public:
  SMS( int from = 0, int to = 0, string text = "" );
  int getTo() const;
  string toString() const;
};

class Mobile;      // forward declaration

class Provider {
private:
  Mobile * list;

public:
  void setList( Mobile * lst );                 // list = lst
  Mobile *Provider :: getMobile ( int nr );  // here it goes wrong 
  void processMessage(  const SMS & sms );
};

class Mobile {
private:
  int phonenr;
  Provider * provider;
  SMS message;
public:
  Mobile( Provider * provider = NULL, int phonenr  = 0);
  void receive ( const SMS & sms );
  void send ( string text, int to );
  string toString() const;
};


int main() {
  Provider prov;
  Mobile mob[10];
  for( int nr = 0; nr < 10; nr++ )
    mob[ nr ] = Mobile( &prov, nr);

  prov.setList( mob );

  mob[1].send( "I am going home now", 9 );
  cout << mob[9].toString() << endl;

  mob[9].send( "Ok, see you soon", 1 );
  cout << mob[1].toString() << endl;

  cin.get();
}

// Implementation for Mobile
Mobile ::  Mobile( Provider * provider, int phonenr )
  : provider(provider), phonenr(phonenr) {
}

void Mobile :: receive ( const SMS & sms ) {
  message = sms;
}

void Mobile :: send( string text, int to ) {
  provider -> processMessage( SMS( phonenr, to, text ) );
}

string Mobile :: toString() const {
  ostringstream os;
  os << "Mobile nr = " << phonenr << " " << message.toString();
  return os.str();
}

// Implementation for Provider
Mobile * Provider :: getMobile( int nr )  {
  return &list[nr];
}

void Provider :: setList( Mobile * lst ) {
    list = lst;
}

void Provider :: processMessage(  const SMS & sms ) {
  int nr = sms.getTo();
  Mobile * goal = getMobile( nr );
  goal -> receive ( sms );
}


//Implementation for SMS
SMS :: SMS( int from, int to, string text )
         : from(from), to(to), text(text) {
}

int SMS :: getTo() const {
  return to;
}

string SMS :: toString() const {
  ostringstream os;
  os << "SMS from " << from << " to " << to << ": ";
  os << text;
  return os.str();
}
coder777 (8439)
Some compiler (like visual c++) allow the extra scope qualification other not (like the gcc).

Just remove Provider :: from line 25.
iluah (5)
Thanks for the quick reply coder777, good to know it was the compiler!
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