[英]error: c++ [map] does not name a type
I've written the following as part of a text command parser for a text adventure game. 我已经将以下内容编写为文本冒险游戏的文本命令解析器的一部分。
I'm attempting to associate a string input by a user to an item in an enum class. 我试图将用户输入的字符串与枚举类中的项相关联。 The following is in my header file:
以下是我的头文件:
#include <iostream>
#include <map>
#include <string>
using namespace std;
enum class Noun
{
// Interrogation subjects
name, // ask the subject his name
base, // where is the base?
attack, // when will the attack be?
invalid
};
map < string, Noun > knownNouns;
knownNouns["name"] = Noun::name;
knownNouns["base"] = Noun::base;
knownNouns["attack"] = Noun::attack;
Noun parseNoun(string &noun)
{
auto n = knownNouns.find(noun);
if ( n == knownNouns.end() ) {
return Noun::invalid;
}
return n->second;
When I put this through the compiler, I get the following: 当我通过编译器,我得到以下内容:
nouns.h:46:1: error: 'knownNouns' does not name a type
knownNouns["name"] = Noun::name;
^
nouns.h:47:1: error: 'knownNouns' does not name a type
knownNouns["base"] = Noun::base;
^
nouns.h:48:1: error: 'knownNouns' does not name a type
knownNouns["attack"] = Noun::attack;
^
nouns.h: In function 'Noun parseNoun(std::string&)':
nouns.h:52:10: error: 'n' does not name a type
auto n = knownNouns.find(noun);
^
nouns.h:53:10: error: 'n' was not declared in this scope
if ( n == knownNouns.end() ) {
^
nouns.h:54:16: error: 'Noun' is not a class or namespace
return Noun::invalid;
^
nouns.h:56:12: error: 'n' was not declared in this scope
return n->second;
^
This is my first time attempting to use maps and enums, and I'm not sure what it is I did wrong. 这是我第一次尝试使用地图和枚举,而且我不确定我做错了什么。 I'm also not terribly familiar with the use of auto vars, so that's a bit of cargo-cult programming on my part.
我对自动变速器的使用也不是非常熟悉,所以这对我来说是一些货物狂热编程。 I'm hoping I understood its implementation and the error will clear once I resolve the type definition problem I'm having.
我希望我理解它的实现,一旦我解决了我遇到的类型定义问题,错误就会清除。
edit: That's embarassing. 编辑:这很令人尴尬。 I copy pasted a mistake that I had already corrected.
我复制粘贴了一个我已经纠正过的错误。 the code still does not compile when (ie, the same issue occurs when)
代码仍然无法编译时(即,同样的问题出现时)
map < string, Noun > knownNouns;
knownNouns["name"] = Verb::name;
knownNouns["base"] = Verb::base;
knownNouns["attack"] = Verb::attack;
is corrected as 被纠正为
map < string, Noun > knownNouns;
knownNouns["name"] = Noun::name;
knownNouns["base"] = Noun::base;
knownNouns["attack"] = Noun::attack;
You can't place non-declaration constructs directly in namespace scope. 您不能将非声明构造直接放在命名空间范围中。
A C++ translation unit is a sequence of declarations. C ++翻译单元是一系列声明。
Non-declaration statements such as assignments must be inside function bodies. 分配等非声明语句必须在函数体内。
Fixed code: 固定代码:
#include <iostream>
#include <map>
#include <string>
using namespace std;
enum class Noun
{
// Interrogation subjects
name, // ask the subject his name
base, // where is the base?
attack, // when will the attack be?
invalid
};
map< string, Noun > knownNouns =
{
{ "name", Noun::name },
{ "base", Noun::base },
{ "attack", Noun::attack }
};
auto parseNoun( string const& noun )
-> Noun
{
// auto n = knownNouns.find(noun);
// if ( n == knownNouns.end() ) {
// return Noun::invalid;
// }
// return n->second;
return Noun::invalid;
}
Here knownNouns
is initialized . 这里
knownNouns
已初始化 。 It's not an assignment, even if the =
looks very much like an assignment. 它不是一个任务,即使
=
看起来非常像一个任务。
You may not initialize map entries statically like: 您可能无法静态初始化地图条目,如:
knownNouns["name"] = Verb::name;
knownNouns["base"] = Verb::base;
knownNouns["attack"] = Verb::attack;
声明:本站的技术帖子网页,遵循CC BY-SA 4.0协议,如果您需要转载,请注明本站网址或者原文地址。任何问题请咨询:yoyou2525@163.com.