How do I remove MacPorts on an "unsupported OS" i.e. El Capitan Public beta?

The MacPorts installation that I had on Yosemite doesn't work on the El Capitan since it isn't supported yet. I want to remove the Port installation here but I'm not able to run any of the Port commands. Does anyone have an idea how to clean it up?

On running any port command, I get the following error:

Error: Current platform "darwin 15" does not match expected platform "darwin 14"
Error: If you upgraded your OS, please follow the migration instructions: https://trac.macports.org/wiki/Migration
OS platform mismatch
    while executing
"mportinit ui_options global_options global_variations"
Error: /opt/local/bin/port: Failed to initialize MacPorts, OS platform mismatch

Solution

I just went ahead and manually removed the files (using rm):

sudo rm -rf /opt/local \
    /Applications/DarwinPorts \
    /Applications/MacPorts \
    /Library/LaunchDaemons/org.macports.* \
    /Library/Receipts/DarwinPorts*.pkg \
    /Library/Receipts/MacPorts*.pkg \
    /Library/StartupItems/DarwinPortsStartup \
    /Library/Tcl/darwinports1.0 \
    /Library/Tcl/macports1.0 \
    ~/.macports

It didn't seem to leave any leftovers or break anything.

One thing to note however is that mactex seems to have been installed in the same directory so that got removed as well. I didn't realize that I had that in the same directory. If you're going to repeat the same steps, keep this in mind.