Forgive me if this is an obvious fix as I am very much a novice when it comes to C++.
For my assignment, we were given some starter code that simulates a command-line crypto trading platform. Originally, you would be prompted to type in commands 1 to 6 to do things like print exchange stats, make an offer, print the wallet and such. For my assignment, I’ve been asked to create an advisor bot that takes in string commands such as ‘help’ and processes this to return the appropriate output.
Naturally, since there was already a system in place to do this with integers as inputs, I tried to tweak the functions (I didn’t do a lot yet) so they take string commands instead and output accordingly.
Before anything else, I would like to know why the function getUserOption and input is underlined red in the while loop of the init function, but in the actual function there are no errors:
This is the contents of the header file
#pragma once
#include <vector>
#include "OrderBookEntry.h"
#include "OrderBook.h"
#include "Wallet.h"
#include <string>
using namespace std;
class MerkelMain
{
public:
MerkelMain();
/** Call this to start the sim */
void init();
private:
void advisorBot();
void printHelp();
void printMarketStats();
void enterAsk();
void enterBid();
void printWallet();
void gotoNextTimeframe();
std::string getUserOption();
void processUserOption(string userOption);
void printCurrentTime();
std::string currentTime;
// OrderBook orderBook{"20200317.csv"};
OrderBook orderBook{"20200601.csv"};
Wallet wallet;
};
This is the cpp file
#include "MerkelMain.h"
#include <iostream>
#include <vector>
#include "OrderBookEntry.h"
#include "CSVReader.h"
#include <string>
using namespace std;
MerkelMain::MerkelMain()
{
}
void MerkelMain::init()
{
int input;
currentTime = orderBook.getEarliestTime();
wallet.insertCurrency("BTC", 10);
while(true)
{
advisorBot();
input = getUserOption();
processUserOption(input);
}
}
void MerkelMain::advisorBot()
{
std::cout << "Please enter a command, or help for a list of commands" << std::endl;
std::cout << "============== " << std::endl;
std::cout << "Current time is: " << currentTime << std::endl;
}
/*void MerkelMain::printMenu()
{
// 1 print help
std::cout << "1: Print help " << std::endl;
// 2 print exchange stats
std::cout << "2: Print exchange stats" << std::endl;
// 3 make an offer
std::cout << "3: Make an offer " << std::endl;
// 4 make a bid
std::cout << "4: Make a bid " << std::endl;
// 5 print wallet
std::cout << "5: Print wallet " << std::endl;
// 6 continue
std::cout << "6: Continue " << std::endl;
std::cout << "============== " << std::endl;
std::cout << "Current time is: " << currentTime << std::endl;
}*/
void MerkelMain::printHelp()
{
std::cout << " The available commands are help, help cmd, prod, min, max, avg, predict, time, step " << std::endl;
}
void MerkelMain::printMarketStats()
{
for (std::string const& p : orderBook.getKnownProducts())
{
std::cout << "Product: " << p << std::endl;
std::vector<OrderBookEntry> entries = orderBook.getOrders(OrderBookType::ask,
p, currentTime);
std::cout << "Asks seen: " << entries.size() << std::endl;
std::cout << "Max ask: " << OrderBook::getHighPrice(entries) << std::endl;
std::cout << "Min ask: " << OrderBook::getLowPrice(entries) << std::endl;
}
}
void MerkelMain::enterAsk()
{
std::cout << "Make an ask - enter the amount: product,price, amount, eg ETH/BTC,200,0.5" << std::endl;
std::string input;
std::getline(std::cin, input);
std::vector<std::string> tokens = CSVReader::tokenise(input, ',');
if (tokens.size() != 3)
{
std::cout << "MerkelMain::enterAsk Bad input! " << input << std::endl;
}
else {
try {
OrderBookEntry obe = CSVReader::stringsToOBE(
tokens[1],
tokens[2],
currentTime,
tokens[0],
OrderBookType::ask
);
obe.username = "simuser";
if (wallet.canFulfillOrder(obe))
{
std::cout << "Wallet looks good. " << std::endl;
orderBook.insertOrder(obe);
}
else {
std::cout << "Wallet has insufficient funds . " << std::endl;
}
}catch (const std::exception& e)
{
std::cout << " MerkelMain::enterAsk Bad input " << std::endl;
}
}
}
void MerkelMain::enterBid()
{
std::cout << "Make an bid - enter the amount: product,price, amount, eg ETH/BTC,200,0.5" << std::endl;
std::string input;
std::getline(std::cin, input);
std::vector<std::string> tokens = CSVReader::tokenise(input, ',');
if (tokens.size() != 3)
{
std::cout << "MerkelMain::enterBid Bad input! " << input << std::endl;
}
else {
try {
OrderBookEntry obe = CSVReader::stringsToOBE(
tokens[1],
tokens[2],
currentTime,
tokens[0],
OrderBookType::bid
);
obe.username = "simuser";
if (wallet.canFulfillOrder(obe))
{
std::cout << "Wallet looks good. " << std::endl;
orderBook.insertOrder(obe);
}
else {
std::cout << "Wallet has insufficient funds . " << std::endl;
}
}catch (const std::exception& e)
{
std::cout << " MerkelMain::enterBid Bad input " << std::endl;
}
}
}
void MerkelMain::printWallet()
{
std::cout << wallet.toString() << std::endl;
}
void MerkelMain::gotoNextTimeframe()
{
std::cout << "Going to next time frame. " << std::endl;
for (std::string p : orderBook.getKnownProducts())
{
std::cout << "matching " << p << std::endl;
std::vector<OrderBookEntry> sales = orderBook.matchAsksToBids(p, currentTime);
std::cout << "Sales: " << sales.size() << std::endl;
for (OrderBookEntry& sale : sales)
{
std::cout << "Sale price: " << sale.price << " amount " << sale.amount << std::endl;
if (sale.username == "simuser")
{
// update the wallet
wallet.processSale(sale);
}
}
}
currentTime = orderBook.getNextTime(currentTime);
}
std::string MerkelMain::getUserOption()
{
std::string userOption = "";
std::string line;
//std::cout << "Type in 1-6" << std::endl;
std::getline(std::cin, line);
try{
userOption = std::stoi(line);
}catch(const std::exception& e)
{
//
}
std::cout << "You chose: " << userOption << std::endl;
return userOption;
}
void printCurrentTime()
{
std::cout << "Current time is: " << currentTime << std::endl;
}
void MerkelMain::processUserOption(string userOption)
{
if (userOption == "help")
{
printHelp();
}
if (userOption == "help cmd")
{
printMarketStats();
}
if (userOption == "prod")
{
enterAsk();
}
if (userOption == "min")
{
enterBid();
}
if (userOption == "max")
{
printWallet();
}
if (userOption == "avg")
{
gotoNextTimeframe();
}
if (userOption == "predict")
{
enterAsk();
}
if (userOption == "time")
{
enterBid();
}
if (userOption == "step")
{
gotoNextTimeframe();
}
}
>Solution :
Your getUserOption() function returns a std::string. This means when you wrote:
input = getUserOption();
In the above statement the right hand side is of type std::string. On the other hand, the left hand side is of type int. So there is mismatch in the type of left hand side and right hand side expressions. Hence the error.
You can solve this by changing the type of variable input to std::string. So replace int input; by:
std::string input; //type changed to std::string