var getValue,setValue;
(function(){
var secret=0;
getValue=function(){
return secret;
};
setValue=function(v){
if(typeof v==="number"){
secret=v;
}
};
}());
getValue();//0
setValue(123);
getValue();//123
setValue(false);
getValue();//123
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getValue()andsetValue()are closures, sharing a variablesecret, so if thesecretis changed in thesetValuefunction,getValue()will of course read thesecretChange accordingly.Isn’t it 0? How did you get 123.