UI: import can be destructive

Hi,

Most of you probably know one of svk's most powerful feature
is the 'import' that actually imports over existing directory,
which allows painless vendor branch updating.

However, It can be destructive, consider you might think:

  svk import //project/trunk /tmp/some-other-code

Would import things into //projec/trunk/some-other-code.
Where as it will kill everything in you trunk and use
that some-other-code as the current content of trunk.  Bad.
Of course it's not so destructive since we have a version
control system.  But it's still annoying, and reminds me
about 'cvs import' which you would definitely use it wrong
once in a while, and that makes you think it's bad software.

So, there are a number of ways to prevent this.  I am wondering
which once annoys the user the least:

* Make import actually do --check-only, and prints out what it
  will do.  but when you import a large project, you will see
  lots of A and will probably ignore the small 'D  trunk'

* Make import ask or stop when there's D happening.  This can
  be annoying and makes the default behaviour non-deterministic.

What do people think?

Cheers,
CLK