undefined method merge

merb datamapper seems to be broken.

$ merb
Loading init file from /home/kristian/workspace/ruby/nightly/config/init.rb
Loading /home/kristian/workspace/ruby/nightly/config/environments/development.rb
:size option is deprecated, use String with :length instead (/usr/lib/ruby/gems/1.8/gems/merb_datamapper-1.0.12/lib/merb/session/data_mapper_session.rb:10)
 ~ Connecting to database...
 ~ Loaded slice 'MerbAuthSlicePassword' ...
 ~ Parent pid: 5790
/usr/lib/ruby/gems/1.8/gems/merb_datamapper-1.0.12/lib/merb_datamapper.rb:61:in `run': undefined method `me开发者_StackOverflow中文版rge' for #<DataMapper::Model::DescendantSet:0xb6f9bd14> (NoMethodError)

Anyone know how to fix this?

I just uninstalled merb and installed it once again, but I am still getting this error.

Try upgrading to Merb 1.0.15, which was just released a few days ago. It adds support for the new DataMapper series and resolves this specific issue.

I believe the gems are on gemcutter now, so you should probably follow these installation instructions:

http://wiki.github.com/merb/merb/howto-install