| fun Long.id() = this | |
| fun String.drop2() = if (length >= 2) subSequence(2, length) else null | |
| fun doSimple1(s: String?) = s?.length == 3 | |
| fun doLongReceiver1(x: Long) = x?.id() == 3L | |
| fun doChain1(s: String?) = s?.drop2()?.length == 1 | |
| fun doIf1(s: String?) = | |
| if (s?.length == 1) "A" else "B" | |
| fun doSimple2(s: String?) = 3 == s?.length | |
| fun doLongReceiver2(x: Long) = 3L == x?.id() | |
| fun doChain2(s: String?) = 1 == s?.drop2()?.length | |
| fun doIf2(s: String?) = | |
| if (1 == s?.length) "A" else "B" | |
| // 0 valueOf |