PHP Internals News: Episode 87: Deprecating Ticks

Thursday, June 3rd 2021, 09:15 BST

In this episode of "PHP Internals News" I chat with Nikita Popov (Twitter, GitHub, Website) about the "Deprecating Ticks" RFC.

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Transcript

Derick Rethans 0:14: Hi I'm Derick, welcome to PHP internals news, a podcast dedicated to explaining the latest developments in the PHP language. This is episode 87. Today I'm talking with Nikita Popov about a much smaller RFC this time: Deprecating Ticks. Nikita, would you please introduce yourself.
Nikita Popov 0:34: Hi Derick, I'm Nikita, and I'm working on PHP core development on behalf of JetBrains.
Derick Rethans 0:40: Let's jump straight into what this RFC is about, and that's the word ticks. What are ticks?
Nikita Popov 0:46: Ticks are a declare directive,. You write declare ticks equals one at the top of your file, and then PHP we'll call a tick function after every statement execution. Or if you write ticks equals two, then as we'll call it the function after every two statement executions.
Derick Rethans 1:05: Do you have to specify which function that calls?
Nikita Popov 1:08: Of course, so there is also a register tick function and unregister tick function and that's how you specify the function that should be called rather the functions.
Derick Rethans 1:17: How does this work, historically, because the RFC talks about the change being made in PHP seven?
Nikita Popov 1:22: Technically ticks work by introducing an opcode after every statement that calls the tick function depending on current count. The difference that was introduced in PHP seven is to what the tick declaration applies. The way PHP language semantics are supposed to work, is that declare directives are always local. The same way that strict types, only applies to a single file, ticks should also only apply to a single file. Prior to PHP seven, it didn't work out way. So if you had declare ticks, somewhere in your file, it would just enable ticks from that point forward. If you included the different file or even if the autoloader was triggered and included a different file that one would also make use of ticks. That