javascript - code-style: Is inline initialization of JS objects ok? -


I often get inline using Initializing (see the example below), especially in a switch statement when I Do not know which cases will be loop hits, I know that it is easy to read compared to the statement.

But is this a good practice or will it affect side-effect or performance? 

 for  (var i in array) {var o = o? O: {}; // init object if it does not exist o [array [i]] = 1; // key-enter code}

Is there a good website to get coding style suggestions?

Another commonly used pattern to do this, or = Use of operator (slightly more readable than your Ternary IMHO): 

  // ... var obj = o || {};

This operator will return to its second operand if it evaluates the first code false , else it will be the first one.

is safe when you expect something, to use it since, because duplicate value null , undefined < / Code>, NaN , 0 , a zero-length string, and of course false .

I used to be useful for setting default values ​​ on function arguments, when definitely expecting to be valid by any function of false values Goes: 

  function testing (arg1) {arg1 = arg1 || "default value"; // ..}

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