Global space

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- PHP Manual
- Namespaces
- Global space

## Global space

(PHP 5 >= 5.3.0, PHP 7, PHP 8)

Without any namespace definition, all class and function definitions are placed into the global space - as it was in PHP before namespaces were supported. Prefixing a name with `\` will specify that the name is required from the global space even in the context of the namespace.

Example #1 Using global space specification

    <?phpnamespace A\B\C;/* This function is A\B\C\fopen */function fopen() {      /* ... */     $f = \fopen(...); // call global fopen     return $f;} ?>