== foo ==
fun foo() {
    "before"
    val b = 1
    fun local(x: Int) {
        val a = x + b
    }
    "after"
}
---------------------
L0:
  1 <START>                                                                     INIT: in: {} out: {}            USE: in: {} out: {}
  2 mark({ "before" val b = 1 fun local(x: Int) { val a = x + b } "after" })
    mark("before")
    r("before")
    v(val b = 1)                                                                INIT: in: {} out: {b=D}
    r(1)                                                                        INIT: in: {b=D} out: {b=D}
    w(b)                                                                        INIT: in: {b=D} out: {b=ID}
    jmp?(L2)                                                                    INIT: in: {b=ID} out: {b=ID}
    d(fun local(x: Int) { val a = x + b })                                                                      USE: in: {b=READ} out: {b=READ}
L2:
    mark("after")
    r("after")
L1:
  1 <END>                                                                       INIT: in: {} out: {}
error:
    <ERROR>
sink:
    <SINK>                                                                                                      USE: in: {} out: {}
=====================
== local ==
fun local(x: Int) {
        val a = x + b
    }
---------------------
L3:
  3 <START>                    INIT: in: {b=ID} out: {b=ID}
    v(x: Int)                  INIT: in: {b=ID} out: {b=ID, x=D}
    w(x)                       INIT: in: {b=ID, x=D} out: {b=ID, x=ID}
  4 mark({ val a = x + b })    INIT: in: {b=ID, x=ID} out: {b=ID, x=ID}
    v(val a = x + b)           INIT: in: {b=ID, x=ID} out: {a=D, b=ID, x=ID}
    mark(x + b)                INIT: in: {a=D, b=ID, x=ID} out: {a=D, b=ID, x=ID}     USE: in: {b=READ, x=READ} out: {b=READ, x=READ}
    r(x)                                                                              USE: in: {b=READ} out: {b=READ, x=READ}
    r(b)                                                                              USE: in: {} out: {b=READ}
    call(+, plus)
    w(a)                       INIT: in: {a=D, b=ID, x=ID} out: {a=ID, b=ID, x=ID}
L4:
  3 <END>                      INIT: in: {b=ID, x=ID} out: {b=ID, x=ID}
error:
    <ERROR>                    INIT: in: {} out: {}
sink:
    <SINK>                     INIT: in: {b=ID, x=ID} out: {b=ID, x=ID}               USE: in: {} out: {}
=====================