It's All About the Goto

on YouTube ↗44m

" summary

Explains how PHP turns source into tokens then an AST then opcodes that Zend executes, and that control flow is implemented as jumps/goto-style opcodes (so conditionals and loops become jumps). Shows tools: tokenizer extension, php-ast visualizer and VLD to inspect opcodes. Notes surprises: PHP7 grows to ~150 opcodes, foreach clones arrays and you cannot jump into language constructs, and branch-aware coverage (Xdebug) is possible but expensive and currently impractical for full projects.

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" chapters (15)

1. 0:00Intro
2. 0:27About Me
3. 1:14Stages
4. 2:14Tokenization
5. 6:29Scanner Rules
6. 13:23Abstract Syntax Tree (formatted)
7. 17:09Byte Code
8. 18:52AST is converted to bytecode
9. 29:19FOR (rewritten)
10. 31:54FOREACH
11. 35:06Complex Loops
12. 36:42Dead Code
13. 38:56Xdebug code coverage output
14. 39:34Xdebug branch coverage display
15. 41:17Recap

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