A Case Study in Incrementing a Language's Major Version - PHP

Explore a case study on incrementing a major version of a programming language, focusing on PHP's transition from version 5 to 7. Learn about the challenges and strategies employed by the PHP team to balance backward compatibility with new features, and compare their approach to other languages. Discover how the team encouraged adoption through incentives and managed potential breaking changes. Examine the impact on existing codebases, migration strategies, and the role of automated tools in the transition process. Gain insights into the decision-making process behind major version updates and the lessons learned from PHP's successful upgrade, which achieved significant adoption rates within two years of release.

Introduction
Version History
Backward Compatibility
Minor Versions
Backward Compatibility Break
Subtle Insidious Changes
Exception Changes
Downstream Users
Migration
Intermediate option
Automated tools
Magic
Future imports
Strict
Perl
PHP Warning Messages
The Catch
Outofband Static Analysis
Give a reason
Open rebellion
Python adoption curve
PHP 7 was fast
Easy answer
Not an option
PHP 7 broke
PHP graveyard
Rust
PHP Roadmap
C
Summary
Questions