deepFreeze
obj1 = {
internal: {}
};
Object.freeze(obj1);
obj1.internal.a = 'aValue';
obj1.internal.a // 'aValue'
// To make obj fully immutable, freeze each object in obj.
// To do so, we use this function.
function deepFreeze(obj) {
// Retrieve the property names defined on obj
var propNames = Object.getOwnPropertyNames(obj);
// Freeze properties before freezing self
propNames.forEach(function(name) {
var prop = obj[name];
// Freeze prop if it is an object
if (typeof prop == 'object' && prop !== null)
deepFreeze(prop);
});
// Freeze self (no-op if already frozen)
return Object.freeze(obj);
}
obj2 = {
internal: {}
};
deepFreeze(obj2);
obj2.internal.a = 'anotherValue';
obj2.internal.a; // undefined
internal: {}
};
Object.freeze(obj1);
obj1.internal.a = 'aValue';
obj1.internal.a // 'aValue'
// To make obj fully immutable, freeze each object in obj.
// To do so, we use this function.
function deepFreeze(obj) {
// Retrieve the property names defined on obj
var propNames = Object.getOwnPropertyNames(obj);
// Freeze properties before freezing self
propNames.forEach(function(name) {
var prop = obj[name];
// Freeze prop if it is an object
if (typeof prop == 'object' && prop !== null)
deepFreeze(prop);
});
// Freeze self (no-op if already frozen)
return Object.freeze(obj);
}
obj2 = {
internal: {}
};
deepFreeze(obj2);
obj2.internal.a = 'anotherValue';
obj2.internal.a; // undefined