Expected unqualified id before int ошибка - ErrorsMaster.ru - большая энциклопедия ошибок и их решений

I got this error «expected unqualified-id before int» in c++ when I was trying to compile it.

void yearlyWithdrawal(int startingAge, int numOfYears), int yearlyAmount, double interestRate)
{
    int age = startingAge;
    int lastAge = startingAge + numOfYears;
    double cash = yearlyAmount;
    cout << "Age | Yearly Plan" << endl;
    cout << "----+----------------" << endl;
    while (age <= lastAge)
    {
        cout.width(3);
        cout << age << " | ";
        cout.width(15);
        cout.precision(2);
        cout.setf(ios::fixed);
        cout << cash << endl;
        if (age != lastAge)
            cash = cash + cash*interestRate / 100.0;
        age++;
    }
    system("pause");
}

I tried to find what went wrong but couldn’t.

asked Dec 9, 2013 at 0:17

Hint:

void yearlyWithdrawal(int startingAge, int numOfYears), int yearlyAmount, double interestRate)
// --------------------------------------------------^

answered Dec 9, 2013 at 0:18

Konrad RudolphKonrad Rudolph

527k130 gold badges930 silver badges1208 bronze badges

void yearlyWithdrawal(int startingAge, int numOfYears), int yearlyAmount, double interestRate)

The ) in the middle of this line could be an obvious pointer to a problem before ‘an int’.

answered Dec 9, 2013 at 0:19

Niels KeurentjesNiels Keurentjes

41.2k9 gold badges98 silver badges135 bronze badges

Источник

Forum
Beginners
expected unqualified-id before ‘int’

expected unqualified-id before ‘int’

Slight compile problems. I’m Linux using g++

Here’s what happens in terminal

john@john-laptop:/media/disk/Cannon$ make
g++ -Wall -O2 -c -o Enemy.o Enemy.cpp
Enemy.cpp:10: error: expected unqualified-id before ‘void’
Enemy.cpp:18: error: expected unqualified-id before ‘void’
Enemy.cpp:24: error: expected unqualified-id before ‘int’
Enemy.cpp:29: error: expected unqualified-id before ‘int’
make: *** [Enemy.o] Error 1

Here’s the source code for Enemy.cpp

#include "Library.h" // Just std libs and SDL stuff and the H file below

ENEMY::ENEMY(ENEMY* enemy)
{
	setName(enemy->getName());
	setHealth(enemy->getHealth());
	setMoney(enemy->getMoney());
}

ENEMY::void createEnemy(char* name, int health, int money, int damage, int x, int y)
{
	setDamage(damage);
	setMoney(money);
	setHealth(health);
	setName(name);
}

ENEMY::void setPosition(int xPosition, int yPosition)
{
	xPos = xPosition;
	yPos = yPosition;
}

ENEMY::int getX()
{
	return xPos;
}

ENEMY::int getY()
{
	return xPos;
}

Source for Enemy.h

// Based off of Stats.h

class ENEMY: public STATS
{
	private:
			char damage;
			int armor;
			int xPos;
			int yPos;
	public:
		//ENEMY();
		ENEMY(ENEMY*);
		void createEnemy(char*, int, int, int, int, int);
		void setPosition(int xPosition, int yPosition);
		int getX();
		int getY();
};

and because this is related to stats i’ll throw that in too

Stats.cpp

#include "Library.h" // Holds all our libraries

// This is based off Stats.h
// For more documentation see Stats.h

void STATS::setWeapon(char *name)
{
	weapon = name;
}

char* STATS::getWeapon()
{
	return weapon;
}

bool STATS::setName(char* newName)
{
	// If empty string return false
	if (strlen(newName) == 0)
		return false;
	
	// If string is bigger than allocated size (30) return false
	if (strlen(newName) > 32)
		return false;
		
	strcpy(name, newName); // If we get past the above apply name settings
	
	return true;
}

char* STATS::getName()
{
	return name;
}

void STATS::setMoney(int amount)
{
	money = amount;
}

int STATS::getMoney()
{
	return money;
}

void STATS::setHealth(int amount)
{
	health = amount;
}

int STATS::getHealth()
{
	return health;
}

and then there’s

Stats.h

// This class is the foundation for both the player & enemies
class STATS
{
	private:
	char name [50]; // A bit more allowing on the allocation
	
	// The rest are self explanatory if you've ever played a game
	int money;
	int health;
	char weapon[30];
	
	public:
	void setWeapon();
	char* getWeapon;
	bool setName(char* newName);
	char* getName();
	void setMoney(int amount);
	int getMoney();
	void setHealth (int amount);
	int getHealth ();
};

Can someone help me solve this, I’ve been on google for about 2 hours now, and I can’t seem to figure this out. I have a feeling it’s the way my classes are setup, but .. I’m not so sure..

Thanks in advance!!

void ENEMY::createEnemy(char* name, int health, int money, int damage, int x, int y)

you always need to write the type of the return value in front of the class name, like you did in Stats.cpp.

Thanks for the help, I see where your going with this, but the problem has gotten a bit worse.

I’ve added the void onto the line. And I still have the above error messages, plus this one

—> Enemy.cpp:3: error: return type specification for constructor invalid

All help is appreciated!

Bump (I hope that’s allowed)

AleaIactaEst wrote:
you always need to write the type of the return value in front of the class name

Always but with the constructor, you can’t specify a return type for it

Enemy.cpp:3: error: return type specification for constructor invalid

This is what the error says

Last edited on

Constructors don’t return values, so do what AleaIactaEst said for every function except the constructor.

Also, I hope that Enemy.cpp somehow includes Enemy.h (it should be including it directly, not relying on
Library.h, if indeed that is gratuitously including it for you).

Topic archived. No new replies allowed.

Источник

Syntax in C++ plays a vital role and even with a slight mistake, it can give birth to a lot of unexpected errors. One of these errors is the “expected unqualified id error” that can arise due to some common oversights while writing your code. In this article, we are going to dive deep into the expected unqualified id error and what can be its possible solutions.

What is an Expected Unqualified Id Error?

The Expected Unqualified Id error is one of the most commonly encountered errors in C++ programming. It is an error that occurs when the code which is written does not match the standards and rules of the programming language.

Why does an Expected Unqualified Id error occur?

The expected unqualified id error mainly occurs due to mistakes in the syntax of our C++ code. Some of the most common reasons for this error are as follows:

Omitted or Misplaced Semicolons
Writing Strings without Quotes
Header Files Not Included
Invalid Variable Declaration
Under or Over-usage of Braces

1. Omitted or Misplaced Semicolons

This type of error is very typical and may arise when we place the semicolon in the wrong place or if our code misses a semicolon.

Example:

C++

#include <iostream>

using namespace std;

class teacher;

{

private:

string num;

public:

void setNum(int num1) { num = num1; }

string getNum() { return num }

};

int main() { return 0; }

Output

error: expected unqualified-id before '{' token
    4 | class teacher;{
      |

The above code produced an error. You will notice that the class ‘teacher’ has a semi-colon and the ‘return num’ statement does not. To solve the error you need to remove the semi-colon from the ‘teacher’ class and add a semi-colon at the end of the ‘return’ statement.

2. Writing string values without quotes

Another common mistake that you can make is specifying the values of the string without quotes. C++ does not accept the string value without quotes and interprets it as a variable and throws the ‘expected unqualified id’ error.

Example:

C++

#include <iostream>

using namespace std;

int main()

{

cout << please enter your age << endl;

cin >> age;

}

Output

error: 'please' was not declared in this scope
    7 |     cout << please enter your age << endl;
      |

We have not enclosed ‘please enter your age’ in quotes which is why this piece of code will produce an error.

3. Header File not Included

C++ has a vast amount of libraries defined inside the header file. To use those libraries, we must first include those header files otherwise an expected unqualified error is encountered.

Example:

C++

int main()

{

cout << "GFG!";

return 0;

}

Output

error: 'cout' was not declared in this scope
    3 |     cout << "GFG!";
      |     ^~~~

4. Invalid Variable Declaration

While writing the code, you should be mindful of not declaring your functions with the same keywords which are reserved by the language.

Example:

C++

#include <iostream>

using namespace std;

int main()

{

int case = 10;

cout << case;

return 0;

}

Output

error: expected unqualified-id before 'case'
    8 |     int case = 10;

In the above example, we used “delete” as our function name which is a reserved keyword. The delete function is an inbuilt function in C++ that is used to deallocate the memory of a class object.

5. Over or Under Usage of Braces

Curly braces in C++ are used to declare various variables and help to determine where the statement begins and where it ends and the scope. The curly braces always come in pairs i.e. opening and closing braces. So if any of them is missing, an error is shown.

Example:

C++

#include <iostream>

using namespace std;

int main()

{

if (true) {

cout << "You choose the black color";

}

else if (false) {

cout << "You choose the purple color";

return 0;

}

Output

error: expected '}' at end of input
   13 | }
      | ^

In the above example, we missed one brace after the if statement which means that the statement is incomplete and will produce the state error.

How to fix the Expected Unqualified Id Error in C++?

Since all of these errors occur due to incorrect syntax, we can avoid these errors by using the correct syntax in our program. Nowadays, many popular code editors contain plugins to check for syntax errors automatically and highlight them even before compilation so it is easy to find and fix these errors.

We can also keep in mind the following points which are one of the most common reasons for this error:

1. Placing Accurate Semi-colons and Braces

Simply placing semi-colons at the end of the statements according to the standards will help in avoiding this error.

Example:

C++

#include <iostream>

using namespace std;

int main()

{

int a = 3;

int b = a % 25;

cout << b << endl;

return 0;

}

In the code above, we placed a semi-colon after every declaration which helps the compiler to understand that the statement ends here and your code will run successfully.

2. Valid Variable Declaration

You should not declare a variable name that starts with a numeric character as it is not allowed. Also, keywords cannot be used as variables and the identifiers must be unique in their scope so keeping that in mind while declaring the variables will help in avoiding these types of errors.

Example:

C++

#include <iostream>

using namespace std;

int main()

{

int abc = 10;

int def = 5;

int ijk = abc * def;

cout << ijk;

return 0;

}

The above code is an example of how you can declare variables to avoid these types of errors.

Last Updated :
29 Mar, 2023

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Источник

Expected unqualified-id is a common error that can occur in various platforms like C/C++, Xcode, and Arduino. This article will assess why it occurs based on different scenarios involving unqualified members of code.

Furthermore, there will also be an analysis of many solutions according to those different scenarios to solve the error. This guide will serve as the ultimate help for you to understand why this error occurs and how it can be fixed.

Contents

Why Is the Expected Unqualified-ID Error Happening?
Why Does the Expected Unqualified-ID Error Occur in C/C++ Languages?
- – Std Namespace and Scope Resolution Operator
- – Invalid Declaration of Variables
- – Invalid Placement of Semicolons
- – Invalid Syntax of Loops
- – Invalid Identifier and Defining Constructors
- – Why Does It Occur in Xcode and Arduino?
How To Fix the Unqualified-id Error?
- – Std Namespace and Scope Resolution Operator
- – Stating the Type of Variable
- – Correct Placement of Semicolons
- – Checking the Syntax of Loops
- – Preventing Invalid Identifiers and Defining Constructors
- – Solving the Issue for Xcode and Arduino
Conclusion

Why Is the Expected Unqualified-ID Error Happening?

The expected unqualified-id error occurs due to several reasons depending on specific circumstances on specific platforms. The common factor in all those reasons is the inadequate role of specific members in a code concerning its implementation. It renders the members ‘unqualified’ for successful implementation and prompts the occurrence of an expected unqualified-id error.

Why Does the Expected Unqualified-ID Error Occur in C/C++ Languages?

Programming languages like C and C++ encounter this error frequently with their compilers. Simple mistakes can cause the inadequate role of members, which can hinder the implementation of the code.

Normal functioning scenarios involve qualified names of members that can refer to namespace members, class members, or enumerators. There are indications associated with these qualified names regarding where they belong.

An expected unqualified-id C or C++ involves unqualified names of members in these languages. They are not located in any namespace and do not warrant a qualification. The scope resolution operator can distinguish unqualified names as it is not used with them. The following is a list of common cases that cause the occurrence of this error in C and C++.

– Std Namespace and Scope Resolution Operator

Using namespace std expected unqualified-id error occurs when the std namespace and scope resolution operator “::” are placed in front of user-declared data names. In another case, it is not advised to use std:: when ‘using namespace std;’ is already placed at the top though it is not a problem to have both. The following is a code example that explains how these actions lead to the error:

#include <iostream>
using namespace std;
char options[] = {};
const char* random_option (options);
{
std::return_val = std::options [rand {array::size options}];
return std::return_val;
};

– Invalid Declaration of Variables

The error can also occur if the data variables are not accurately declared based on the syntax. The code example above does not state the type of its “return_val” variable.

– Invalid Placement of Semicolons

Accurate placement of semicolons is an important thing that has to be ensured which is why their invalid placement can cause the compiler to encounter the error. The code example above contains a semicolon after “random_option (options).”

This conveys to the compiler that the process of defining the function is finished now, and a function body will not be given to it afterward. It means that every member of the code inside the {} afterward is not taken as part of the function definition by the compiler.

In addition, an invalid placement of semicolons can result in the display of another error by a compiler. This error is displayed as an expected unqualified-id before ‘(‘ token) and is associated with (). It can signify that a semicolon is wrongly placed with the bracket and should be removed.

– Invalid Syntax of Loops

The error can also occur in association with the invalid syntax of loops like ‘for’ and ‘while.’ There are multiple reasons for the occurrence of the error with loops. The most common reason involves the placement of those loops outside the relevant function body.

A compiler displays the error as an expected unqualified-id before for that can mean that a ‘for’ loop is placed outside a function body. The following is a snippet of a code example that shows how the error can occur with a ‘for’ loop placed outside an ‘int main’ function:

for (i = 0; i < days; i++)
{
// loop body
}
int main()
{
…
return 0;
}

Furthermore, the error associated with a ‘while’ loop is displayed as an expected unqualified-id while by a compiler. This can mean that the while loop is placed outside a function body. Here is a code example of a snippet that shows how that can happen:

while (i = 0; i < days; i++)
{
// loop body
}
int main()
{
…
return 0;
}

– Invalid Identifier and Defining Constructors

The error can also occur while defining constructors when a compiler misreads the code as an instantiation of an object. It displays the error as an expected unqualified-id before int because now, a list of arguments is expected to be passed to the constructor. In this case, int does not qualify as a valid identifier, so it cannot be passed. The following is a snippet of a code example that shows how the error can occur:

using namespace std;
Days (int days, int month, int year)

– Why Does It Occur in Xcode and Arduino?

The error occurs in Xcode due to unqualified names of members that are not located in any namespace and do not warrant a qualification. Xcode is an integrated development environment that develops software for Apple devices only. Therefore, the expected unqualified-id Xcode error is specific to them only.

Similarly, an expected unqualified-id Arduino error also occurs due to unqualified names of members. The only difference is that this happens in Arduino, which is an open-source environment for designing microcontrollers for digital devices.

How To Fix the Unqualified-id Error?

Unqualified-id error has multiple solutions including omitting namespace std, stating the type of variable and correct placement of semicolons. Some other easy fixes are checking the syntax of loops and preventing invalid identifiers.

– Std Namespace and Scope Resolution Operator

The std namespace is where all the standard library types and functions are defined. Therefore, std:: only needs to be written in front of a name if that name is defined inside of the standard library namespace. It needs to be removed from the start of those names that are declared by the user.

It is recommended to practice the conventional ways and then pick one style. You can write ‘using namespace std;’ and then avoid std:: in front of those names that are from inside of std. Or else, you can omit writing ‘using namespace std;’ at the top and then write std:: in front of all those names that are used from the standard library. The following is a snippet for the above code example in which ‘using namespace std;’ is omitted:

#include <iostream>
char options[] = {};
…

– Stating the Type of Variable

The declaration of a variable requires the user to state its type. In this way, the compiler can understand if ‘options’ in the code example above is meant to be an array of single characters or an array of strings. The following is a snippet for the above code example in which the ‘char’ type is given to the variable ‘options’:

char options[] = {};
const char* random_option (options);

– Correct Placement of Semicolons

A semicolon should not be placed after the lines of code that define a function. Those lines are followed by the relevant function body within {} that is taken as part of that function. Therefore, your code should convey this to the compiler by not having a semicolon at the end of such lines. Here is the correct snippet of the above code example for this:

const char* random_option (options)
{
std::return_val = std::options [rand {array::size options}];
return std::return_val;
};

– Checking the Syntax of Loops

The occurrence of the error in association with loops can be prevented by placing them within a function body. It does not matter if the function is ‘int main’ or any other as long as the loops are parts of the relevant function body. Here is how you can accurately place the ‘for’ and ‘while’ loops within a function body:

int main()
{
for (i = 0; i < days; i++)
{
// loop body
}
return 0;
}
int main()
{
while (i = 0; i < days; i++)
{
// loop body
}
return 0;
}

– Preventing Invalid Identifiers and Defining Constructors

The occurrence of error associated with defining constructors and involving ‘int’ can be prevented. It involves the usage of the scope resolution operator before ‘int’ so that it is not considered an invalid identifier. In this way, a constructor can be accurately defined with an acceptable involvement of ‘int’ for a compiler. Here is how you can do that:

using namespace std;
Days::Days (int days, int month, int year)

– Solving the Issue for Xcode and Arduino

The error associated with Xcode and Arduino can be solved by turning the unqualified names of members in code into qualified ones. This varies based on circumstances and primarily involves ensuring aspects of an accurate syntax. Examples of such aspects include valid placement of semicolons and declaration of variables.

Conclusion

This article sheds a spotlight on the expected unqualified-id error by covering why it occurs and how it can be fixed. Here are the important takeaway points:

It occurs due to the inadequate role of specific members in a code concerning its implementation.
An expected unqualified-id involves unqualified names of members that are not located in any namespace and do not warrant a qualification.
A working code includes qualified names of members that refer to namespace members, class members, or enumerators.
The error also occurs in Xcode and Arduino due to the same reason of unqualified names of members in a code.
The error in these platforms can be solved by turning the unqualified names of members in code into qualified ones.

These solutions are always available for you to check which one works for you.

Источник

The expected unqualified-id before is a common C++ error that developers often face. This comprehensive guide will help you understand the error, its causes, and provide step-by-step solutions to fix it. Additionally, we have included an FAQ section to address any lingering questions you may have.

Understanding the Error
Common Causes of the Error
Step-By-Step Solutions
Solution 1: Checking for Missing Semicolons
Solution 2: Fixing Variable or Function Names
Solution 3: Correcting Preprocessor Directives
Solution 4: Fixing Namespace Issues
Solution 5: Resolving Compiler Compatibility Issues
FAQ
Related Links

Understanding the Error

The expected unqualified-id before error occurs when the C++ compiler encounters an unexpected token while parsing your code. This token can be a keyword, a symbol, or any other identifier that the compiler does not expect at that particular position in your code. To resolve this error, you must identify the unexpected token and correct it, which may involve fixing a typo, adding a missing character, or modifying the structure of your code.

Common Causes of the Error

Here are some common causes of the expected unqualified-id before error:

Missing semicolons.
Incorrect variable or function names.
Incorrect preprocessor directives.
Namespace issues.
Compiler compatibility issues.

Step-By-Step Solutions

Below are step-by-step solutions to resolve the expected unqualified-id before error.

Solution 1: Checking for Missing Semicolons

One common cause of this error is a missing semicolon at the end of a statement. To fix this, go through your code and ensure that all statements have a semicolon at the end.

// Correct
int x = 5;
int y = 10;

// Incorrect
int x = 5
int y = 10;

Solution 2: Fixing Variable or Function Names

Another common cause of this error is incorrectly named variables or functions. Make sure your variable and function names do not start with a number, contain spaces, or use reserved keywords.

// Correct
int my_function(int a, int b) {
    return a + b;
}

// Incorrect
int 1_function(int a, int b) {
    return a + b;
}

Solution 3: Correcting Preprocessor Directives

The error may also occur due to incorrect preprocessor directives. Make sure you use the correct syntax for including header files, defining macros, and using conditional compilation.

// Correct
#include <iostream>

// Incorrect
include <iostream>

Solution 4: Fixing Namespace Issues

This error can also be caused by incorrect namespace usage. Check if you are using the correct namespace for the functions or classes you are using.

// Correct
#include <iostream>

int main() {
    std::cout << "Hello, World!" << std::endl;
    return 0;
}

// Incorrect
#include <iostream>

int main() {
    cout << "Hello, World!" << endl;
    return 0;
}

Solution 5: Resolving Compiler Compatibility Issues

Lastly, the error may be caused by using a feature that is not available in your compiler version. If this is the case, consider updating your compiler or modifying your code to use a feature that is compatible with your compiler version.

FAQ

Question 1: Can this error appear in other programming languages?

Yes, similar errors can appear in other programming languages. The exact error message and syntax may vary from language to language, but the basic concept remains the same: the compiler has encountered an unexpected token.

Question 2: What is the difference between an «unqualified-id» and a «qualified-id»?

An «unqualified-id» is an identifier that is not preceded by any namespace or scope resolution operators, while a «qualified-id» includes the namespace or scope resolution operators.

Yes, missing header files can cause this error. If a required header file is not included, the compiler will not recognize the functions or classes defined in that header file, which may lead to the expected unqualified-id before error.

Question 4: How can I prevent this error from occurring in the future?

To prevent this error from occurring in the future, follow best coding practices, such as using meaningful variable and function names, properly including header files, and always double-checking your code for missing semicolons or other syntax errors.

Question 5: Is it possible that my compiler is causing this error?

It is possible, but unlikely. Most modern C++ compilers are quite reliable and produce accurate error messages. If you suspect that your compiler is causing the error, try using a different compiler or updating your current compiler to the latest version.

C++ Programming: Comprehensive C++ reference with examples.
C++ Standard Library: Complete documentation of C++ standard library headers.
C++ Core Guidelines: Official guidelines for writing modern, safe, and efficient C++ code.
Stack Overflow: A popular Q&A platform where you can ask questions related to C++ and programming in general.

Источник

expected unqualified-id before ‘int’

What is an Expected Unqualified Id Error?

Why does an Expected Unqualified Id error occur?

1. Omitted or Misplaced Semicolons

C++

2. Writing string values without quotes

C++

3. Header File not Included

C++

4. Invalid Variable Declaration

C++

5. Over or Under Usage of Braces

C++

How to fix the Expected Unqualified Id Error in C++?

1. Placing Accurate Semi-colons and Braces

C++

2. Valid Variable Declaration

C++

Why Is the Expected Unqualified-ID Error Happening?

Why Does the Expected Unqualified-ID Error Occur in C/C++ Languages?

– Std Namespace and Scope Resolution Operator

– Invalid Declaration of Variables

– Invalid Placement of Semicolons

– Invalid Syntax of Loops

– Invalid Identifier and Defining Constructors

– Why Does It Occur in Xcode and Arduino?

How To Fix the Unqualified-id Error?

– Std Namespace and Scope Resolution Operator

– Stating the Type of Variable

– Correct Placement of Semicolons

– Checking the Syntax of Loops

– Preventing Invalid Identifiers and Defining Constructors

– Solving the Issue for Xcode and Arduino

Conclusion

Table of Contents

Understanding the Error

Common Causes of the Error

Step-By-Step Solutions

Solution 1: Checking for Missing Semicolons

Solution 2: Fixing Variable or Function Names

Solution 3: Correcting Preprocessor Directives

Solution 4: Fixing Namespace Issues

Solution 5: Resolving Compiler Compatibility Issues

FAQ

Question 1: Can this error appear in other programming languages?

Question 2: What is the difference between an «unqualified-id» and a «qualified-id»?

Question 4: How can I prevent this error from occurring in the future?

Question 5: Is it possible that my compiler is causing this error?