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  1. local mytable = {}
  2.  
  3. local mt = {}
  4.  
  5. function mt.__newindex(t,k,new_value)
  6.     local previous_value = mt[k]
  7.     rawset(mt,k,new_value)
  8.  
  9.     if previous_value and new_value == nil then
  10. 	    print "__remove() triggered"
  11.     end
  12. end
  13. mt.__index = mt
  14.  
  15. setmetatable(mytable, mt)
  16.  
  17. mytable.key = 123
  18. print(mytable.key)
  19.  
  20. mytable.key = nil
  21. print(mytable.key)
  22. -- your code goes here
Success #stdin #stdout 0s 15008KB
comments (?)
stdin 
Standard input is empty
stdout 
123
__remove() triggered
nil
https://ideone.com/eCOal3
language:
Lua (luac 5.3.3)
created:
7 years ago
visibility:
public

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