JavaScript trick: `===` can be used to detect two object "a" and "b" if there
are pointed to the same object. An object in JavaScript is kind like `ref
object` in nim and every data mutation directly to `a` can be accessed from `b`
when they are `===` equal. It's much faster to just compare `a === b` to know
they are identical than comparing every properties.
Suppose in Nim, I have a type:
type A = ref object
x: int
let a = A(x: 1)
let b = a
echo a == b
echo a.unsafeAddr.repr
echo b.unsafeAddr.repr
Run
when it compares with `==`, it compares values and returns `true`. But their
pointers are different:
true
ptr 0x10fbabc28 --> ref 0x10fbd1048 --> [x = 1]
ptr 0x10fbabc30 --> ref 0x10fbd1048 --> [x = 1]
Run
Since we learnt the trick of JavaScript, and noticed that both `a` and `b`
refers to the ref `ref 0x10fbd1048`. Can I skip value comparing and just figure
out that they are the same ref?
