Hello world, it's Wednesday, July 15, 2026, and here's what happened This Week in PHP Internals.
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This week's top story is a brand-new keyword knocking on the door: extension. One week after Larry Garfield floated Kotlin-style extension functions at the scalar-methods RFC, Holly Schilling arrived with working prototypes of Swift-style class extensions — born, she says, out of a Discord conversation — and it became the biggest thread of the week at 26 messages. The idea: add methods to a class you don't own — extension \DateTimeImmutable gives every date an isWeekend() — and, in a later phase, put methods on scalars, so "hello" gets a length(). She published 3 draft RFCs as gists, implementation included. Michael Morris asked the obvious first question, writing: "Looking at Swift's extension syntax I fail to see anything it adds not covered by the above." — the above being inheritance and traits. Holly drew the line clean: "An extension is essentially the reverse of a trait." With a trait, the author of the class decides; with an extension, the user of the class decides.
