ruby - Create hash-of-hashes using structure of the default hash -

i have following code:

default = {:id => 0, :detail =>{:name=>"default", :id => ""}} employees = {}  nr = (0..3).to_a  nr.each |n|     employee = default     employee[:id] = n     employee[:detail][:name] = "default #{n}"     employee[:detail][:id] = "key-#{n}"     employees[n] = employee end puts employees 

i expect values key :id in :detail hash key-0, key-1, key-2.

you need change:

default = { :id=>0, :detail=>{ :name=>"default", :id=>"" } } 

to

def default   {}.merge(:id=>0, :detail=>({}.merge(:name=>"default", :id=>""))) end 

but, hey, while we're @ may ruby-ize rest:

employees = (0..3).map |n|     employee = default     employee[:id] = n     employee[:detail][:name] = "default #{n}"     employee[:detail][:id] = "key-#{n}"     employee end   #=> [{:id=>0, :detail=>{:name=>"default 0", :id=>"key-0"}},   #    {:id=>1, :detail=>{:name=>"default 1", :id=>"key-1"}},   #    {:id=>2, :detail=>{:name=>"default 2", :id=>"key-2"}},   #    {:id=>3, :detail=>{:name=>"default 3", :id=>"key-3"}}]  

let's confirm making deep copies of default:

employees[0][:detail][:id] = "cat" employees   #=> [{:id=>0, :detail=>{:name=>"default 0", :id=>"cat"}},   #    {:id=>1, :detail=>{:name=>"default 1", :id=>"key-1"}},   #    {:id=>2, :detail=>{:name=>"default 2", :id=>"key-2"}},   #    {:id=>3, :detail=>{:name=>"default 3", :id=>"key-3"}}]  

you'd more commonly see written:

employees = (0..3).map |n|   default.merge(:id=>n, :detail=>{:name=>"default #{n}", :id=>"key-#{n}"}) end   #=> [{:id=>0, :detail=>{:name=>"default 0", :id=>"cat"}},   #    {:id=>1, :detail=>{:name=>"default 1", :id=>"key-1"}},   #    {:id=>2, :detail=>{:name=>"default 2", :id=>"key-2"}},   #    {:id=>3, :detail=>{:name=>"default 3", :id=>"key-3"}}]  

as suggested other answers, this:

class object   def deep_copy     marshal.load(marshal.dump(self))   end end 

then write:

default = { :id=>0, :detail=>{ :name=>"default", :id=>"" } } employees = (0..3).map |n|   default.deep_copy.merge(:id=>n, :detail=>{:name=>"default #{n}",     :id=>"key-#{n}"}) end   #=> [{:id=>0, :detail=>{:name=>"default 0", :id=>"key-0"}},   #    {:id=>1, :detail=>{:name=>"default 1", :id=>"key-1"}},   #    {:id=>2, :detail=>{:name=>"default 2", :id=>"key-2"}},   #    {:id=>3, :detail=>{:name=>"default 3", :id=>"key-3"}}]  

this has advantage that, if change default, no other changes needed.