I would like to understand how the built-in function property works. What confuses me is that property can also be used as a decorator, but it only takes arguments when used as a built-in function ... When accessing a property, the "dot" syntax (images.main) supposes, I think, that it already exists.
I had such problems without Typescript, in "vanilla" Javascript, where I tried to access data as: return json.property[0].index where index was a variable. But it interpreted index, resulting in a: cannot find property "index" of json.property[0] My best guess would be to use a private member variable, a property for that variable with get and init accessors (not auto-implemented) and the setter member function. 2 In str's answer, value 'undefined' will be returned instead of the set default value if the property is undefined. This sometimes can cause bugs.
Property Caretaker Positions, The following will make sure the defaultVal will always be returned when either the property or the object is undefined. 129 RequiredIf validation attribute I've written a that requires a particular property value when a different property has a certain value (what you require) or when a different property has anything but a specific value. This is the code that may help: Descriptors like property need to be in the type's dictionary to work their magic. So those in a class definition primarily affect the behaviour of instances of the class, with minimal effect on the behaviour of the class itself (since the class is the type of the instances). While it might work in this specific case, it's simply bad practice.
Property Caretaker Positions, What if he wants to distinct by a different property somewhere else? For sure he can't override Equals twice, can he? :-) Apart from that, it's fundamentally wrong to override equals for this purpose, since it's meant to tell whether two objects are equal or not. In my situation I had my property auto initialize a command in a ViewModel for a View. I changed the property to use expression bodied initializer and the command CanExecute stopped working. Here's what it looked like and here's what was happening.
