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B.1 Passing Optional Parameters by Reference

You can now pass optional parameters by reference. For example:

function updateAddress(&$address = 'NULL') {



}

In PHP 4, you could declare a parameter as either optional or pass-by-reference, but not both. PHP 5 removes this limitation.



    		Upgrading to PHP 5
    		Preface
    		Chapter 1. Introduction
    		Chapter 2. Object-Oriented Programming
    		Chapter 3. MySQL
    		Chapter 4. SQLite
    		Chapter 5. XML
    		Chapter 6. Iterators and SPL
    		Chapter 7. Error Handling and Debugging
    		Chapter 8. Streams, Wrappers, and Filters
    		Chapter 9. Other Extensions
    		Chapter 10. PHP 5 in Action
    		Appendix A. Introduction to XML
    		Appendix B. Additional New Features and Minor Changes
    		B.1 Passing Optional Parameters by Reference
    		B.2 New E_STRICT Error Setting
    		B.3 Treating Strings as Arrays Causes Errors
    		B.4 CLI Now Allows Individual Line Processing
    		B.5 CLI Always Provides argv and argc
    		B.6 Oracle (oci8) Extension Functions Renamed
    		B.7 New Configuration Directives
    		B.8 Updated COM Extension
    		B.9 Apache 2 Correctly Sets PATH_TRANSLATED
    		B.10 strrpos( ) Uses the Entire Needle
    		B.11 Windows 95 Support Dropped
    		B.12 old_function Eliminated
    		Appendix C. Installing PHP 5 Alongside PHP 4
    		Colophon