undeclared identifier

音标

英式音标：[ˌʌndɪˈkleəd aɪˈdentɪfaɪə]

美式音标：[ˌʌndɪˈklerd aɪˈdentɪfaɪər]

基本释义

undeclared identifier 是一个计算机编程和编译器相关的术语，意思是“未声明的标识符”。
在程序代码中，如果使用了一个变量、函数或常量，但事先没有进行声明或定义，编译器就会报错提示 undeclared identifier。

翻译

中文：未声明的标识符

英文：identifier not declared

用法说明

多用于编程语言的错误提示，特别是在 C、C++、Pascal 等编译型语言中。

触发该错误通常有以下几种情况：

使用了未定义或未包含头文件中的函数或变量。

变量作用域超出了使用范围。

拼写错误导致与原有声明不一致。

短语搭配

undeclared identifier error —— 未声明标识符错误

fix undeclared identifier —— 修复未声明的标识符

undeclared identifier warning —— 未声明标识符警告

例句（10句）

The compiler shows an undeclared identifier error when you forget to declare a variable.

In C++, using a function without including the proper header file will cause an undeclared identifier.

If you mistype a variable name, the system may report it as an undeclared identifier.

The student could not run the code because of an undeclared identifier in line 25.

An undeclared identifier usually indicates that the variable has not been defined in the current scope.

Adding the correct header file fixed the undeclared identifier problem.

Beginners often encounter the undeclared identifier error when learning C programming.

The compiler treated the misspelled keyword as an undeclared identifier.

Debugging revealed that the cause of failure was an undeclared identifier in the loop.

Always declare your variables before using them to avoid the undeclared identifier error.

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