How to return a dynamic allocated struct of arrays in a method?

Question

I have the following struct and method in the public part of my headerfile:

struct InputtedInstructions
{
    string name;
    string arg1;
    string arg2;
    string arg3;
};
InputtedInstructions get_instruction(vector<string>& text, int count);

then in my cpp file:

      Instructions::InputtedInstructions Instructions::get_instruction(vector<string>& vec, int counter)
{   
    int ListPosition = 0;
    InputtedInstructions* InputList = new InputtedInstructions[counter];
    while (ListPosition != counter)
    {

        string text = vec.at(ListPosition);
        istringstream iss(text);
        string command, arg1, arg2, arg3;

        int CommaAmount = count(text.begin(), text.end(), ',');

        if (CommaAmount == 2)
        {
            while( iss >> command >> arg1 >> arg2 >> arg3)
            { 
                InputList[ListPosition].name = command;
                InputList[ListPosition].arg1 = arg1;
                InputList[ListPosition].arg2 = arg2;
                InputList[ListPosition].arg3 = arg3;
                ListPosition++;
            }
        }
//same thingfor 3 commas, 4, etc. 
        return InputList;

My issue is on that return statement down there. it wants me to add [] to the end of it. but I want to return the entire InputList array. Is there something glaringly obvious I am doing wrong? Thanks for your help.

score 0 · Answer 1 · answered Oct 02 '13 at 15:42

0

You'll need to return a vector<InputtedInstructions> and not worry about heap allocation.

answered Oct 02 '13 at 15:42

Paul Evans

27,315
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score 0 · Answer 2 · answered Oct 02 '13 at 15:42

The function is declared to return one InputtedInstructions:

InputtedInstructions get_instruction(vector<string>& text, int count);`

But its implementation wants to return a pointer to an InputtedInstructions:

InputtedInstructions* InputList = new InputtedInstructions[counter];

score -1 · Accepted Answer · answered Oct 02 '13 at 15:40

-1

Change your declaration to

InputtedInstructions* get_instruction(vector<string>& text, int count);

And make the definition to be

Instructions::InputtedInstructions* Instructions::get_instruction(vector<string>& vec, int counter)
{

// blah blah

}

answered Oct 02 '13 at 15:40

CS Pei

10,869
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27
46

Awesome. Worked perfectly. Cant believe I didnt see that. – cmonnats23 Oct 02 '13 at 15:44
@cmonnats23 Don't forget to upvote and select the answers that work for you :) – Oct 02 '13 at 15:50
@KevinCadieux I would upvote but I dont have enough "reputation" to upvote yet. But I did mark yours as the correct one since you were first and it worked! – cmonnats23 Oct 03 '13 at 05:18
@cmonnats23 Actually it was John Smith's answer. But thanks for selecting it! I didn't remember you needed reputation to upvote. Sorry about that. – Oct 03 '13 at 15:16

How to return a dynamic allocated struct of arrays in a method?

3 Answers3