delta_hashes.rb

# add value from param to task if:
# - its in the list
# - its in the params so sending nil will nil it but sending nothing will leave it alone
# do some conversion on the value as well

{"hours" => ->(hours){hours_points_converter(hours)},
 "parked" => ->(parked){parked == "1" ? true : false},
 "description" => nil,
 "tag_list" => nil,
 "status_id" => ->(id){id.to_i},
 "position" => ->(p){p.to_i}
}.each{|key, value| task[key] = value.nil? ? params[key] :
 value.call(params[key]) if params.keys.include?(key)}

def hours_points_converter(hours)
 # something here
 hours
end