错误：在 C++ 中返回之前预期的非限定 ID

error : expected unqualified-id before return in c++

提问by user2774480

when I want to compile I get : Probléme : expected unqualified-id before "return" return 0; about last line : erreur:expexted declaration before { token

当我想编译时，我得到： 问题：在“返回”之前预期不合格的 id 返回 0；关于最后一行：错误：{令牌之前的expexted声明

I left the code unchanged just the middle part I changed... whats the problem??? here is my code:

我保留了代码不变，只是我更改了中间部分......有什么问题？？？这是我的代码：

---

---

#include <iostream>
using namespace std;

int main()
{
  cout << "Pensez a un personnage : Mlle Rose, le Professeur Violet, "
       << "le Colonel Moutarde," << endl
       << "le Reverend Olive ou Mme Leblanc." << endl << endl;

  cout << "Votre personnage a-t-il des moustaches (1 : oui, 0 : non) ? ";
  bool moustaches;
  cin >> moustaches;

  cout << "Votre personnage porte-t-il des lunettes ? ";
  bool lunettes;
  cin >> lunettes;

  cout << "Votre personnage porte-t-il un chapeau ? ";
  bool chapeau;
  cin >> chapeau;

  cout << "Est-ce que votre personnage est un homme ? ";
  bool homme;
  cin >> homme;

  cout << "==> Le personnage auquel vous pensez est ";

  if (chapeau) {
    /*******************************************
     * Completez le programme a partir d'ici.
     *******************************************/
    cout << "le Professeur Violet";

    else if (moustaches) {
        cout << "le Colonel Moutarde";
    }
    else if (not lunettes) {
        cout << "Mlle Rose";
    }
    else if (homme) {
        cout <<"le Révérend Olive";
    }
    else {
        cout <<"Mme Leblanc";
    }

    /*******************************************
     * Ne rien modifier apres cette ligne.
     *******************************************/
  }

  cout << endl;

  return 0;
}


----------

回答by Niko

Just for the sake of people who landed here for the same reason I did:

只是为了那些和我一样的原因登陆这里的人：

Don't use reserved keywords

不要使用保留关键字

I named a function in my class definition delete(), which is a reserved keyword and should not be used as a function name. Renaming it to deletion() (which also made sense semantically in my case) resolved the issue.

我在我的类定义中命名了一个函数 delete()，它是一个保留关键字，不应用作函数名称。将其重命名为 delete() （在我的情况下在语义上也有意义）解决了这个问题。

For a list of reserved keywords: http://en.cppreference.com/w/cpp/keyword

有关保留关键字的列表：http: //en.cppreference.com/w/cpp/keyword

I quote: "Since they are used by the language, these keywords are not available for re-definition or overloading. "

我引用：“由于它们被语言使用，这些关键字不可用于重新定义或重载。”

回答by 0x499602D2

if (chapeau) {

You forgot the ending brace to this ifstatement, so the subsequent else ifis considered a syntax error. You need to add the brace when the ifstatement body is complete:

您忘记了此if语句的结束大括号，因此后续语句else if被视为语法错误。当if语句体完成时，您需要添加大括号：

if (chapeau) {
    cout << "le Professeur Violet";
}
else if (moustaches) {
    cout << "le Colonel Moutarde";
}
// ...

回答by CS Pei

You need to move " }" before the line of cout << endl;to the line before the first else.

您需要将 " }" 之前的行移动cout << endl;到第一个之前的行 else。

回答by ChuckCottrill

Suggestions:

建议：

• use consistent 3-4 space indenting and you will find these problems much easier
• use a brace style that lines up {} vertically and you will see these problems quickly
• always indent control blocks another level
• use a syntax highlighting editor, it helps, you'll thank me later

• 使用一致的 3-4 个空格缩进，你会发现这些问题更容易
• 使用垂直排列 {} 的大括号样式，您会很快看到这些问题
• 总是缩进控制阻止另一个级别
• 使用语法高亮编辑器，它会有所帮助，稍后您会感谢我

for example,

例如，

type
functionname( arguments )
{
    if (something)
    {
        do stuff
    }
    else
    {
        do other stuff
    }
    switch (value)
    {
        case 'a':
            astuff
            break;
        case 'b':
            bstuff
            //fallthrough //always comment fallthrough as intentional
        case 'c':
            break;
        default: //always consider default, and handle it explicitly
            break;
    }
    while ( the lights are on )
    {
        if ( something happened )
        {
            run around in circles
            if ( you are scared ) //yeah, much more than 3-4 levels of indent are too many!
            {
                scream and shout
            }
        }
    }
    return typevalue; //always return something, you'll thank me later
}