Closure is a locally declared variable related to a function which stays in memory when the function has returned.
For example:
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functiongreet(message){
console.log(message);
}
functiongreeter(name,age){
returnname+" says howdy!! He is "+age+" years old";
}
// Generate the message
varmessage=greeter("James",23);
// Pass it explicitly to greet
greet(message);
Thisfunctioncan be better represented by using closures
functiongreeter(name,age){
varmessage=name+" says howdy!! He is "+age+" years old";
returnfunctiongreet(){
console.log(message);
};
}
// Generate the closure
varJamesGreeter=greeter("James",23);
// Use the closure
JamesGreeter();
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