Why are functions atomic?

["Martin v. Löwis"]

Michael schrieb:
> A bit more info, but still no clear picture about why functions are
> mutable but have immutable copy symantics.  There are arguments why
> functions should be immutable, but the decision was to make user-
> defined functions mutable.  My question is still: why the present
> ummutable copy symantics?

The answer is really really simple. The implementation of copy predates
mutability. When the copy code was written, functions *were* immutable.
When functions became mutable, the copy code was not changed, and
nobody noticed or complained.

Regards,
Martin