Accessing a property of an uninitialized instance results in a Runtime error

[xwu (Xiaodi Wu)]

On the behavior of variables in top-level code

The variables in top-level code behave weirdly. They are declared in the global scope, but are initialized serially, like local variables in a normal function. This allows some interesting pieces of code to compile, such as: print(x) var x = 32 This program will print 0. The basic value types are automatically initialized, so they have a value. However, if x is a class, this results in a crash. Clearly, this is not an ideal situation. You shouldn't be able to use variables before they are init…