Magic Constants¶

Constants which hold information about the current location of the code.

Those constants are magic, because they have a constant syntax, yet their value may change, even during the execution of the code.

__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 function name, or {closure} for anonymous functions.
__CLASS__ The class name. The class name includes the namespace it was declared in (e.g. FooBar). 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. FooBar).
__METHOD__ The class method name.
__NAMESPACE__ The name of the current namespace.

Those constants are case insensitive. All those syntax will work : __METHOD__, __method__, __meTHod__.

<?php

function foo() {
    // shows foo
    echo __FUNCTION__;
}

function goo() {
    // shows goo
    echo __FUNCTION__;
}

?>

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