Rule 6.1.7: in case of using "implicit backing property" scheme, the name of real and back property should be the same

[petertrr]

Kotlin has a mechanism of backing properties.
In some cases implicit backing is not enough and it should be done explicitly:

private var _table: Map<String, Int>? = null
val table: Map<String, Int>
    get() {
        if (_table == null) {
            _table = HashMap() // Type parameters are inferred
        }
        return _table ?: throw AssertionError("Set to null by another thread")
    }

In this case the name of backing property (_table) should be the same to the name of real property (table), but should have underscore (_) prefix.
It is one of the exceptions from the identifier names rule