Further #to_proc Abuse

Everybody loves to abuse #to_proc. The Symbol#to_proc extension has even been baked in to Ruby 1.9.

Why not continue the duck typing abuse? Let's build a cheap ActiveRecord knock-off for Enumerable:

my_peeps.find_all(&{:last_name => "Palmer"})  appointments.find_all(&{:description => /billable/i, :time => (start_time..end_time)})  my_socks.any?(&{:status => 'washed'}) 

The implementation is simple.

class Hash; def to_proc   proc { |obj| self.inject(true) { |m,(k,v)| m && v === obj.send(k) } } end; end 

Of course, I wouldn't try to argue that it's as useful as Symbol#to_proc. Fun to play with, though. I'm using it in a RubyOSA script that I'm building for Colleen. For completeness, this version performs a little better if the hash has many terms and a lot of records will be filtered out:

class Hash; def to_proc     proc { |obj| self.inject(nil) { |_,(k,v)| v === obj.send(k) || (break false) } } end; end