Add element to rails has_many relation "dynamically" -

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having following models:

class card < activerecord:base   # ...whatever   belongs_to :model end  class model < activerecord:base   # attribute: rank   has_many  :cards end

considering following code:

  mod = model.new   card = card.first   an_attribute = "rank"   another_attribute = "cards"    mod.send("#{an_attribute}=", 1) # works fine, ok   mod.cards << card      # works fine well, ok   mod.send("#{another_attribute}<<", card) # not work, hence question

the last line of code returns error undefined method 'cards<<'

so question is: how can append card element mod.cards while accessing cards has_many relation via variable, i.e. storing name of association in variable ?

mod.send("#{another_attribute}").push(card)

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