Ruby pop an element from a hash table? -


i looking @ http://ruby-doc.org/core-1.9.3/hash.html , there not appear pop method? think missing though... 

if (x = d['a']) != nil   d.delete('a')  end

if know key, use delete directly if hash doesn't contain key, nil back, otherwise whatever stored there

from doc linked to:

h = { "a" => 100, "b" => 200 } h.delete("a")                              #=> 100 h.delete("z")                              #=> nil h.delete("z") { |el| "#{el} not found" }   #=> "z not found"

there shift deletes , returns key-value pair:

hsh = hash.new  hsh['bb'] = 42 hsh['aa'] = 23 hsh['cc'] = 65  p hsh.shift  => ["bb", 42]

as can seen, order of hash order of insertion, not key or value. doc

hashes enumerate values in order corresponding keys inserted.


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