On Mon, 27 Oct 2014, Eliot Miranda wrote:

> See my message earlier in the thread.  Via a per-object isImmutable bit.

So you would set the bit for the CompiledMethod and all literals 
(including sub-arrays, floats, integers, booleans etc)?

Does the set immutability bit also mean that the object can't be swapped 
with #become:?

Levente