> For the complete documentation index, see [llms.txt](https://phper.shujuwajue.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://phper.shujuwajue.com/php-gao-ji-te-xing/mo-zhu-chang-91cf28-magic-constants.md).

# 魔术常量(Magic constants)

* \_\_LINE\_\_ = 该常量所在的行号
* \_\_FILE\_\_ = 该常量所在代码文件的绝对路径
* \_\_DIR\_\_ = 该常量所在代码文件所在的目录的绝对路径，= dirname(\_\_FILE\_\_), PHP 5.3 新增
* \_\_FUNCTION\_\_ 所在函数的函数名
* \_\_CLASS\_\_ 类名，包括命名空间，如果用在 trait 中，该常量的值为 use 该 trait 的类的类名。
* \_\_TRAIT\_\_ = 所在的trait的名字（包括命名空间）
* \_\_METHOD\_\_ = 所在方法的名称，命名空间\类名::函数名
* \_\_NAMESPACE\_\_ = 所在命名空间的名字


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