javascript - Does defining a frequently used string as a variable improve performance? -


this question has answer here:

in languages, used strings defined variables/constants, called instead of literal strings. same javascript? in particular, have frequent use of string 'none'. instead of writing literal 'none' everywhere in code, improve performance if define:

var none = 'none';

and use none everywhere in code? or, there way intern literal string expression evaluated once?

literal strings automatically interned javascript compilers. var = 'hello' , var b = 'hello' pointing @ same copy of 'hello' string in memory, no need further optimization on part.

the way make sure different string objects created same string value defining each 1 via string global object, i.e.:

var = new string('hello'); var b = new string('hello');

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