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roave/function-fqn-replacer
===========================

Replaces relative references to internal functions with absolute references

15690[1 PRs](https://github.com/Roave/FunctionFQNReplacer/pulls)

Since Feb 13Compare

[ Source](https://github.com/Roave/FunctionFQNReplacer)[ Packagist](https://packagist.org/packages/roave/function-fqn-replacer)[ RSS](/packages/roave-function-fqn-replacer/feed)WikiDiscussions Synced today

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Function FQN Replacer
=====================

[](#function-fqn-replacer)

This utility provides a way to replace relative references of functions in function calls with absolute references.

Rationale
---------

[](#rationale)

As explained in [this twitter convo](https://twitter.com/Ocramius/status/811504929357660160) and [this article](https://veewee.github.io/blog/optimizing-php-performance-by-fq-function-calls/), PHP is resolving relative function references at call time.

This is relatively normal, as PHP, by design, cannot make decisions on which file defines which functions, because all opcode caching is local to single scripts, and not to a project.

In addition to that, PHP can only apply optimizations about internal function calls when those calls happen either in the global namespace, or are fully qualified name (FQN) calls.

Here's an example of the opcodes generated for an `call_user_func()` call without and with FQN reference:

```