Ugly First Crack at some Metaprogramming

Hey - this is pretty ugly and probably not even considered Metaprogramming, but have a look/laugh and please suggest a more elegant way:
Basically, I just want to loop through an array of variables to look for in the params hash and set them to instance variables with the same name or set them to ‘’ if non-existant in the hash:
[:criteria, :sort_by, :ord].each { |key| eval("@#{key} = params[:#{key}] || ‘’") }

all this does is just evaluate the following lines:

@criteria = params[:criteria]
@sort_by = params[:sort_by]

etc…

Better ideas?

Thanks

I'm not sure what this is buying you.

You might consider using Object#instance_variable_set instead of eval.