I'm preparing to write a C++ application for OS X with a Cocoa front end. To get started, I've been watching videos on Cocoa / Swift / Interface Builder. I found a tutorial here making a simple tip calculating app. My thoughts were to start small and convert this example application from using a Swift model to a C++ model.

However, I'm running into an issue with the Swift compiler not finding the unordered_map include file. It doesn't seem to have any issue with the vector include and so my first instinct was that the C++11 compiler option was not set. It turns out it is, and I'm still not certain why I get this. Do my C++ files need to be compiled separately with the GCC or Clang compilers?

C++ .h:

#ifndef __TipCalculator__TipCalcModel__
#define __TipCalculator__TipCalcModel__

#include <stdio.h>

#include <unordered_map>
#include <vector>

using std::unordered_map;
using std::vector;



class TipCalcModel
{

private:

    double _total;
    double _taxPct;
    double _subtotal;


public:

    TipCalcModel(double total, double taxPct) : _total(total), _taxPct(taxPct) {};



    unordered_map<int, double>* returnPossibleTips();

    inline double getSubtotal() { return _total / (_taxPct + 1); }

    inline double calcTipWithTipPct(double tipPct) { return _subtotal * tipPct; }

};

#endif /* defined(__TipCalculator__TipCalcModel__) */

C++ .cpp:

#include "TipCalcModel.h"

#include <unordered_map>
#include <vector>

using std::unordered_map;
using std::vector;



unordered_map<int, double>* TipCalcModel::returnPossibleTips()
{
    unordered_map<int, double>* possTipMap = new unordered_map<int, double>;

    vector<double> possPct;
    possPct.push_back(0.15);
    possPct.push_back(0.18);
    possPct.push_back(0.20);

    for (vector<double>::const_iterator pctIter = possPct.cbegin(); pctIter !=         possPct.cend(); ++pctIter)
    {
        possTipMap->insert(std::make_pair(*pctIter * 100, calcTipWithTipPct(*pctIter)));
    }


    return possTipMap;

}

My attempt at a Wrapper for the C++ code.

.h:

#ifndef TipCalculator_TipCalcModelWrapper_h
#define TipCalculator_TipCalcModelWrapper_h


#import <Foundation/Foundation.h>
#include "TipCalcModel.h"


TipCalcModel *tipCalcModel;

@interface CPlusPlusTipCalc : NSObject

- (void) dealloc;

+ (NSString*) returnPossibleTips;

+ (double) getSubtotal;

+ (double) calcTipWithTipPct : (double) tipPct;

@end

#endif

.mm:

#import <Foundation/Foundation.h>

#include "TipCalcModelWrapper.h"
#include "TipCalcModel.h"



@implementation CPlusPlusTipCalc
- (id)init {
    if(self = [super init]) {
    tipCalcModel = new TipCalcModel(0, 0.0);
    }
    return self;
}
- (void) dealloc {
    if(tipCalcModel != NULL) delete tipCalcModel;
}

+ (NSString*) returnPossibleTips {

    unordered_map<int, double>* map = tipCalcModel->returnPossibleTips();


    unordered_map<int, double>::const_iterator mapKey = map->cbegin();

    NSString* retString;


    while (mapKey != map->cend())
    {
        NSString* intermediateString = [NSString stringWithFormat:@"%d %f\n", mapKey-    >first, mapKey->second];

        retString = [retString stringByAppendingString:intermediateString];

        ++mapKey;
    }

    return retString;
}

+ (double) getSubtotal {
    return tipCalcModel->getSubtotal();
}

+ (double) calcTipWithTipPct : (double) tipPct {
    return tipCalcModel->calcTipWithTipPct(tipPct);
}


@end

My header bridge file only contained the following (and now am not sure if this is correct, either):

#include "TipCalcModelWrapper.h"

There could be numerous places I'm going wrong here. Any help and explanation is greatly appreciated. If you have any good resources for hybrid C++ and Cocoa - please post!!

I'm using Xcode 6.1.1.

Thank you for your time!