FILE: thisOfExtensionProperty.kt
    public abstract interface A : R|kotlin/Any| {
    }
    public abstract interface B : R|kotlin/Any| {
        public abstract val b: R|kotlin/Boolean|
            public get(): R|kotlin/Boolean|

    }
    public final val R|A|.check_1: R|kotlin/Boolean|
        public get(): R|kotlin/Boolean| {
            ^ (this@R|/check_1| is R|B|) && this@R|/check_1|.R|/B.b|
        }
    public final val R|A|.check_2: R|kotlin/Boolean|
        public get(): R|kotlin/Boolean| {
            ^ (this@R|/check_2| is R|B|) && this@R|/check_2|.R|/B.b|
        }