C++ Visual Studio 2010, compile error C3867 when implementing dynamic stack

问题

Currently working on an assignment for my datastructures class in university using stacks with dynamic memory allocation. Currently I'm getting a compile error C3867 saying I'm missing a function call from an argument list. I'm not really understanding where this error is coming from / I'm having trouble identifying what exactly is my error in my code; so I was wondering if someone might be kind enough to explain to me what it is, and maybe a friendly tip to remember so I can not have this happen again.

also, I apologize for the poor formatting, I've never posted here before sorry if its hard to read. :(

code posted below.

Thanks, and regards. :P

Header File:

#ifndef STACK_H
#define STACK_H
#include <iostream>
#include <iomanip>

struct Node
{
    Node *nextPtr;
    int value;
};

class Stack
{
public: 
    //Constructors and Deconstructers Here
    Stack(); //Default Constructor
    ~Stack(); //Default Deconstructor

    //logical methods || functions here
    bool isEmpty(void); //prototype checks if stack is empty

    //stack operations || function prototypes here
    void push(int); //prototype to push values of type int onto the stack
    int pop(); //prototype to pop values off of the stack and return a value
    int top(); //prototype to return the top value
private:
    Node *topPtr; //pointer to class Node Object, specifically for the top of the stack
};   

#endif

Class File:

#include "CPTN278_A3_Stack_Arsenault.h"

using namespace std;
Stack::Stack()
{
    topPtr = 0; //set the top pointer equal to zero.
}

Stack::~Stack()
{
    while (!Stack::isEmpty())
    {
        Stack::pop();
    }
}

bool Stack::isEmpty()
{
    if(top == 0)
    {
        return true;
    }
    else
    {
        return false;
    } 
}

void Stack::push(int valueTMP)
{
    Node *itemPtr = new Node; 
    itemPtr->nextPtr = topPtr; 
    itemPtr->value = valueTMP;
    topPtr = itemPtr;
    return;
}

int Stack::pop()
{
    int returnValue; //unintialized int
    Node *itemPtr; //unintialized pointer to node
    returnValue = topPtr->value;
    itemPtr = topPtr;
    topPtr = itemPtr->nextPtr;
    delete itemPtr;
    return returnValue;
}

int Stack::top(void)
{
    return topPtr->value; //**this is where my error is being thrown**
}

回答1:

bool Stack::isEmpty()
{
    if(top == 0) // <-- here is the problem
    {
        return true;
    }
    else
    {
        return false;
    } 
}

top is a function, to check its result you need top(). But I think you should be testing topPtr instead.

回答2:

Before you had:

bool Stack::isEmpty()
{
    if(top == 0) <-- top is a function, did you mean 'topPtr'?
    {
        return true;
    }
    else
    {
       return false;
    } 
}

Fix:

bool Stack::isEmpty()
{
    return topPtr == 0;
}

That's your only build error. I'm not sure why you or the compiler thought it was in the top method. That's perfectly fine. Also there's no need to write:

if (expression_that_is_true_or_false)
    return true;
else
    return false;

Just do:

return expression_that_is_true_or_false;

I might be borderline preaching style here, but try to get used to understanding expressions this way. Expressions involving logical operators like ==, !=, &&, ||, <, >, etc. evaluate to true or false, so there is no need to do conditional branching only to then return what the expression originally evaluated to in the first place.

Oh and I realize this is homework, but check out std::stack later in your free time if you haven't already.

回答3:

In function Stack::isEmpty(), something wrong with top.

bool Stack::isEmpty()
{
  if(top == 0) // here
  {
    return true;
  }
  else
  {
    return false;
  } 
}

I think it should be as below:

  if(topPtr==0)
  ...

来源：https://stackoverflow.com/questions/9525815/c-visual-studio-2010-compile-error-c3867-when-implementing-dynamic-stack

标签

c++

pointers

compiler-errors

visual-c++-2010