2017-04-04 18:01 GMT+02:00 Ben Coman <btc@openinworld.com>:

I believe Esteban's point Its not so much whether the VM has it
(since they are essentially the same VM + extra C-libs for Pharo)
but whether the Squeak Image is using it.

Squeak does use primitiveFindSubstring, but a difference is attached to ByteString rather than String.
That was added to Squeak 2015.05.01.�� Squeak String seems to have never used the primitive (since 2005).��

You can make experiment. Replace fallback code with "self primitiveFailed" and call this method from comment examples. It works in SqueakVM. And it fails with latest PharoVM.

Actually just remove this method from ByteString. And many debuggers will approve that method is used