Js function declaration form

problem description

when looking at other people"s project code, I found that there is still such a way to declare a function, and it is also very interesting in the way it is called. It can be called with variables and corresponding numbers with variables. What is this writing and why can it be used? [variable] is this form unique to the object? when I printed the test object, I found that the object had a key name, that is, "0, 1, 2", and each key corresponds to a function

related codes

Javascript

Jul.07,2021

the new syntax of ES6 (sugar).

 -sharp calculation attribute name


										
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						MySQL Query :  SELECT * FROM `codeshelper`.`v9_news` WHERE status=99 AND catid='6' ORDER BY rand() LIMIT 5 
 MySQL Error : Disk full (/tmp/#sql-temptable-64f5-1b3aa98-e77f.MAI); waiting for someone to free some space... (errno: 28 "No space left on device") 
 MySQL Errno : 1021 
 Message :  Disk full (/tmp/#sql-temptable-64f5-1b3aa98-e77f.MAI); waiting for someone to free some space... (errno: 28 "No space left on device") 
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