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Magic Constants

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Magic constants are distinguished by their __CONSTANTNAME__ form.

There are currently eight magical constants that change depending on where they are used. For example, the value of __LINE__depends on the line that it’s used on in your script.

These special constants are case-insensitive and are as follows:

Name| Description | —— | —— |__LINE__ | The current line number of the file. |__FILE__ | The full path and filename of the file with symlinks resolved. If used inside an include, the name of the included file is returned. |__DIR__ | The directory of the file. If used inside an include, the directory of the included file is returned. This is equivalent to dirname(__FILE__). This directory name does not have a trailing slash unless it is the root directory. |__FUNCTION__ | The current function name |__CLASS__ | The class name. The class name includes the namespace it was declared in (e.g. Foo\Bar). When used in a trait method, __CLASS__ is the name of the class the trait is used in. |__TRAIT__ | The trait name. The trait name includes the namespace it was declared in (e.g. Foo\Bar). |__METHOD__ | The class method name. |__NAMESPACE__ | The name of the current namespace. |

Most common use case for these constants is debugging and logging

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Magic constants:
* Magic Constants
* Difference between FUNCTION and METHOD
* Difference between CLASS get class and get called class
* File Directory Constants
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