hash - for each loop in hashes in ruby? -

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i'm new in ruby i'm learning hashes , below code behaving hell please 

hash = {"15" => {:a=>"a_15", :b=>"b_15", :c=>"c_15 ", :d=>"pass"},         "16" => {:a=>"d_16", :b=>"e_16", :c=>"f_16 ", :d=>"fail"}}    mod= {} h = {} hash.each |k,v|   v.each |x,y|     mod[x] = y   end   h[k] = mod   # mod={}    # don't want use technique                # creates new object not required end  p h

expected output: 

{"15" => {:a=>"a_15", :b=>"b_15", :c=>"c_15 ", :d=>"pass"},  "16" => {:a=>"d_16", :b=>"e_16", :c=>"f_16 ", :d=>"fail"}}

actual output :

{"15"=> {:a=>"d_16", :b=>"e_16", :c=>"f_16 ", :d=>"fail"},  "16"=> {:a=>"d_16", :b=>"e_16", :c=>"f_16 ", :d=>"fail"}}

please !!!! :(

after first iteration got:

h == {"15" => {:a=>"a_15", :b=>"b_15", :c=>"c_15 ", :d=>"pass"}}

where value is reference mod. during second iteration change mod, apparently changes value of h['15'], is referencing mod.

to quick fix that: 

h[k] = mod.dup

the above produce cloned version of mod. check described behaviour, might run original code , do:

h.values.each { |v| puts v.__id__ }

the above print the identifiers of objects , you’ll see keys of resulting array referencing same object.


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