scope issues

[AndroidZ]

I want line 152 of intstack.cpp to be possible without restructuring my entire program. Is there a way to do this?

intstack.h

#pragma once

#include <stdlib.h>
class IntStack
{
    //int DEFAULT_current_element;
    int current_element;
    int* st_arr;
public:
    const static int DEFAULT_STACK_CAPACITY = 100;
    size_t stack_capacity;
    //default constructor
    IntStack() : /*DEFAULT_STACK_CAPACITY(100),*/ st_arr(new int [DEFAULT_STACK_CAPACITY]), stack_capacity(DEFAULT_STACK_CAPACITY), current_element(0)
    {
    }
    //overloaded constructor
    IntStack(int n) : stack_capacity(n), st_arr(new int [DEFAULT_STACK_CAPACITY]), current_element(0)
    {
    }
    //destructor
	~IntStack() {delete [] st_arr;}
    void reset();
    void push(int n);
    void push(int a[], size_t array_size);
    int pop();
    void pop(int a[], size_t n);
    int top();
    size_t size();
    size_t capacity();
    void double_capacity();
    bool is_full();
    bool is_empty();
    //void evaluate(std::string com);
    friend IntStack print_stack(IntStack* pstack);
};

main.cpp

#include <iostream>
#include <stdlib.h>
#include <string>
#include <cassert>
#include "intstack.h"

using namespace std;

void command_list();
void evaluate(string com, IntStack* st);
IntStack create_stack(char capans, int cap);
int main()
{
    string command;
    //int st_num = 0;

    char capans = 'y';
    int cap;
    cout << "Welcome to the stack program. To begin with, a stack must be created. \n";
    cout << "Would you like to use the default capacity of 100? y/n \n";
    cin >> capans;
    if (capans == 'n'){
        cout << "Enter capacity: \n";
        cin >> cap;
    }
    IntStack st = create_stack(capans, cap);

    int arr_size;
    cout << "Now an array of integers needs to be created. How many integers will this array have? \n";
    cin >> arr_size;
    int arr[arr_size];
    int el;
    for (int i = 0; i < arr_size; i++){
        cout << "Enter element " << i << " of the array \n";
        cin >> el;
        arr[i] = el;
    }

    cout << "Here are your command choices: \n";
    cout << "push     //to push ints to stack \n";
    cout << "pop      //to pop off elements \n";
    cout << "top      //to get top element of stack \n";
    cout << "print    //to print a stack \n";
    cout << "size     //to get the size of a stack \n";
    cout << "capacity //to see the capacity fo a stack \n";
    cout << "reset    //reset stack \n";
    cout << "commands //to display this command list \n";
    cout << "exit     //to exit the program \n\n";
    //int result;
    while(1==1){
        cout << "> ";
        cin >> command;
        evaluate(command, &st);

    }
    return 0;
}

intstack.cpp

#include <string>
#include "intstack.h"
#include <iostream>

using namespace std;

IntStack print_stack(IntStack* pstack){
    for (int i = 0; i < pstack->current_element; i++){
        cout << pstack->st_arr[i] << "\n";
    }
}

int IntStack::top(){
    current_element--;
    int temp = current_element;
    current_element++;
    return st_arr[temp];
}

size_t IntStack::size(){
    return current_element;
}

size_t IntStack::capacity(){
    return stack_capacity;
}

void IntStack::reset(){
    for (int i = 0; i < stack_capacity; i++){
        st_arr[i] = NULL;
    }
    current_element = 0;
}

void IntStack::push(int n){
    if (current_element == stack_capacity){
        cout << "Stack full... doubling capacity \n";
        double_capacity();
    }
    st_arr[current_element] = n;
    current_element++;
}

void IntStack::push( int arr[], size_t array_size ){
    for (int i = 0; i < array_size; i++){
        if (current_element == stack_capacity){
            double_capacity();
        }
        push(arr[i]);
    }
}

int IntStack::pop(){
    if (current_element == 0){
        cerr << "STACK EMPTY\n";
    }
    --current_element;
    int temp = st_arr[current_element];
    st_arr[current_element] = NULL;
    return temp;
}

void IntStack::pop( int a[], size_t n ){
    if (current_element > 0)
        current_element--;
    for (int idx = 0; idx < n; idx++){
        if (current_element == 0){
            cerr << "STACK EMPTY\n";
        }
        a[idx] = st_arr[current_element];
        st_arr[current_element] = NULL;
        if(current_element>0)
            current_element--;
    }
    //cout << "after popping, i is " << i << "\n"; //DB
}

int* allocate(int num);
void deallocate(int* old);

void IntStack::double_capacity(){
    int* new_mem = allocate(stack_capacity * 2);

    for (int i = 0; i < current_element; i++){
        new_mem[i] = st_arr[i];
    }
    deallocate(st_arr);
    st_arr = new_mem;
    stack_capacity *= 2;
}

int* allocate(int num){
    int* new_mem = new int[num];
    return new_mem;
}

void deallocate(int* old){
    delete[] old;
}

bool IntStack::is_full(){
    if(current_element == 100)
        return true;
    else
        return false;
}

bool IntStack::is_empty(){
    if(current_element != 0)
        return false;
    else
        return true;
}

//-------------------------
//---Interface Functions---
//-------------------------

void command_list(){
    cout << "Here are your command choices: \n";
    cout << "push     //to push ints to stack \n";
    cout << "pop      //to pop off elements \n";
    cout << "top      //to get top element of stack \n";
    cout << "print    //to print a stack \n";
    cout << "size     //to get the size of a stack \n";
    cout << "capacity //to see the capacity fo a stack \n";
    cout << "reset    //reset stack \n";
    cout << "commands //to display this command list \n";
    cout << "exit     //to exit the program \n\n";
}

void evaluate(string com, IntStack* st_ ){
    int c;

    if (com == "push")    { c = 0; }
    if (com == "pop")     { c = 1; }
    if (com == "top")     { c = 2; }
    if (com == "print")   { c = 3; }
    if (com == "size")    { c = 4; }
    if (com == "capacity"){ c = 5; }
    if (com == "reset")   { c = 6; }
    if (com == "commands"){ c = 7; }
    if (com == "exit")    { c = 8; }
    else                  { c = 9; }

    IntStack st = *st_;
    switch (c)
    {
        case 0:
            int x;
            cout << "Enter int: \n";
            cin >> x;
            st.push(x);
            break;
        case 1:
            break;
        case 2:
            break;
        case 3:
            //print_stack(&st);
            break;
        case 4:
            break;
        case 5:
            break;
        case 6:
            break;
        case 7:
            command_list();
            break;
        case 8:
            exit(1);
        case 9:
            break;
    }
}

IntStack create_stack(char capans, int cap ){
    if (capans == 'y'){
        IntStack st;
        return st;
    }
    if (capans == 'n'){
        IntStack st(cap);
        return st;
    }
}

[ne555]

void evaluate(string com, IntStack &st);

[AndroidZ]

Right under my nose, thanks. Updated.
But why won't any of my commands but "exit" work?

[ne555]

IntStack st = *st_; You are making a copy there.
Just use the pointer. st_->push(x);

[AndroidZ]

Thanks.

It still doesn't output the cout though, and the "command" command doesn't do anything. It was working earlier, but now it's not, and I don't know why.