Great point, I'll edit my comment to say "(or its equivalent)", instead of "(that precise sequence of characters, no matter what you've redefined true and false to be)". Not sure why I originally wrote it that way.
The issue isn't that they're constants, but that GP called them "true" and "false" and assigned the opposite values you'd expect. You can break it in exactly the same way with variables: https://play.golang.org/p/EVU84l0A57I
Kinda crazy to me that Go doesn't reserve the words "true" and "false", but ¯\_(ツ)_/¯
`!` is added to values in most languages as a shorthand for saying "give me the opposite boolean value of this. So `!true` would equal `false`
Some people add two exclamation points as a shorthand to cast a value to a boolean. So if you wanted to see if something was 'truthy', you could say `!!truthyValue` and it would return ` true` instead of the value itself. Literally what your asking the language is "give me the opposite boolean value of the opposite boolean value of `truthyValue`"
Now you can probably see why three exclamation points is silly, it's not giving you anything that a single exclamation point wouldn't give you. Both `!truthyValue` and `!!!truthyValue` evaluate to false, you are literally saying "give me the opposite boolean value of the opposite boolean value of the opposite boolean value of `truthyValue`"
The example in Go is intentionally misleading because Go lets you reassign the values for `true` and `false`. It's going through all the same steps I described above, but it's starting with a value opposite of what you think it is
