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lua:meta [2015/07/19 13:48] – niziakprogramming:lua:meta [2020/07/03 09:48] (current) – ↷ Page moved from lua:meta to programming:lua:meta niziak
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 ===== Metamethods ===== ===== Metamethods =====
-  * **%%__index%%** is called when key in table doesn't exists. **%%__index%%** can be a function or another table - fallback table. Fallback table can have metatable which points to another fallback table and so on. It is possible to create very long fallback table chain. +[[http://lua-users.org/wiki/MetatableEvents]] 
-  * **%%__newindex%%** is called when value to not existsing key (contains **nil**) is assigned. If key exists, method is not called.+ 
 +[[http://lua-users.org/wiki/MetamethodsTutorial]]   
 + 
 +  * **%%__index%%** - is called when key in table is accessed. **%%__index%%** can be a function or another table - fallback table. Fallback table can have metatable which points to another fallback table and so on. It is possible to create very long fallback table chain. 
 +    * **%%__index%% = function (table, key)**, return value of fucntion is returned as result. 
 +    * **%%__index%% = table** 
 +    * to access table key without invoking %%__index%% methamethod use **rawget(table,key)** 
 + 
 +  * * **%%__newindex%%** is called when new value is assigned to key key 
 +    * **%%__newindex%% = function (table, key ,value)** 
 +    * to set new value without invoking methamethod, use **rawset(table, key, value)** 
   * **%%__metatable%%** when set, metatable is hidden. Value of **%%__metatable%%** is returned instead of original metatable.   * **%%__metatable%%** when set, metatable is hidden. Value of **%%__metatable%%** is returned instead of original metatable.
   * **%%__call%%** - if somebady calls table as function, this metamethod will be called   * **%%__call%%** - if somebady calls table as function, this metamethod will be called
-  * **%%__tostring%%** - +  * **%%__tostring%%** - when **tostring(table)** is called 
 +  * **%%__len%%**
  
 ===== Synctatic sugar ===== ===== Synctatic sugar =====