>>= etc.

[StefanKarpinski]

Currently >>=, <<= and >>>= parse as operators but aren't defined. However, think that like += and its ilk, we need these built into the parser, no?

[JeffBezanson]

No, the only one that didn't work is >>>=, this was a small oversight. The others work. They are converted to x = x>>n, so there doesn't need to be a definition for >>=.

Do we want to change this, for example so that += can be defined to update its first argument in place?

[StefanKarpinski]

Do we want to change this, for example so that += can be defined to update its first argument in place?

For bits types this doesn't make sense but for non-immutables, this does make reasonable enough sense. However, anything you're applying an operator like += to is arguably number-like and should have immutable semantics.