Command Parsing Class

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#include <iostream>

#include <vector>

#include <string>

using namespace std;

class commandParser

{

       bool DebugMode; //prints errors if true

       string InvalidCommandMessage;

       vector<string> Commands;

public:

       commandParser(bool debugMode=false, string invalidCommandMessage="You entered an invalid command") { DebugMode=debugMode; InvalidCommandMessage=invalidCommandMessage; }

       ~commandParser() {}

       void AddCommand( const string& cmd ) { Commands.push_back(cmd); }

      

       void RemoveCommand( const string& );

       void RemoveCommand( int );

       void PrintAllCommands() { for (int i=0;i<Commands.size();i++) cout << Commands[i] << endl; }

       bool IsACommand( const string& );

       string FormatInputCommand( const string& );

};

void commandParser::RemoveCommand( int index )

{

       //error protection - don't trust the user

       if (index > Commands.size()-1)

       {

              if (DebugMode) { cout << "Attempt to remove a command with an index greater than all added commands" << endl; }

              return;

       }

       Commands.erase(Commands.begin() + index);

}

void commandParser::RemoveCommand ( const string& cmd )

{

       for (int i=0;i<Commands.size();i++)

              if (Commands[i].compare(cmd) == 0) //same strings

              {

                     Commands.erase(Commands.begin() + i);

                     return; //removed so return

              }

      

       if (DebugMode) cout << "Command '" << cmd << "' deletion request failed - non-existant" << endl;

}

bool commandParser::IsACommand ( const string& cmd )

{

       for (int i=0;i<Commands.size();i++)

              if (Commands[i].compare(cmd) == 0)

                     return true;

       return false;

}

string commandParser::FormatInputCommand( const string& cmd )

{

       string retval;

       retval.assign(cmd);

       //set lowercase

       for (int i=0;i<retval.length();i++)

              tolower(retval[i]);

       return retval;

}

int main()

{

       //set up some commands

       commandParser *CommandParser = new commandParser(true);

      

       CommandParser->AddCommand("hi");

       CommandParser->AddCommand("goto");

       CommandParser->AddCommand("kill");

       CommandParser->AddCommand("march");

       CommandParser->AddCommand("seventy");

       CommandParser->AddCommand("remove this");

       CommandParser->AddCommand("pyramid");

       cout << "First Commands:" << endl;

       CommandParser->PrintAllCommands();

       CommandParser->RemoveCommand("remove this");

       CommandParser->RemoveCommand(3); //march

       cout << "\nNon-removed Commands:" << endl;

       CommandParser->PrintAllCommands();

       cout << "\nUser Input (enter \"exit\" to close)" << endl;

       string userInput = "";

       while (true)

       {

              cin >> userInput;

              if (userInput.compare("exit")==0) return 0;

              if (CommandParser->IsACommand((CommandParser->FormatInputCommand(userInput))))

                     cout << "Correct command" << endl;

              else cout << "Incorrect command" << endl;

       }

       return 0;

}

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