library /*isNonNullableByDefault*/;
import self as self;
import "dart:core" as core;
import "dart:collection" as col;

static method nullAwareListSpread(core::List<core::String>? list) → dynamic {
  list = block {
    final core::List<core::String> #t1 = <core::String>["foo"];
    final core::Iterable<core::String>? #t2 = list;
    if(!(#t2 == null))
      #t1.{core::List::addAll}{Invariant}(#t2{core::Iterable<core::String>}){(core::Iterable<core::String>) → void};
  } =>#t1;
}
static method nullAwareSetSpread(core::Set<core::String>? set) → dynamic {
  set = block {
    final core::Set<core::String> #t3 = col::LinkedHashSet::•<core::String>();
    #t3.{core::Set::add}{Invariant}("foo"){(core::String) → core::bool};
    final core::Iterable<core::String>? #t4 = set;
    if(!(#t4 == null))
      #t3.{core::Set::addAll}{Invariant}(#t4{core::Iterable<core::String>}){(core::Iterable<core::String>) → void};
  } =>#t3;
}
static method nullAwareMapSpread(core::Map<core::int, core::String>? map) → dynamic {
  map = block {
    final core::Map<core::int, core::String> #t5 = <core::int, core::String>{};
    #t5.{core::Map::[]=}{Invariant}(0, "foo"){(core::int, core::String) → void};
    final core::Map<core::int, core::String>? #t6 = map;
    if(!(#t6 == null))
      #t5.{core::Map::addAll}{Invariant}(#t6{core::Map<core::int, core::String>}){(core::Map<core::int, core::String>) → void};
  } =>#t5;
}
static method main() → dynamic {
  self::nullAwareListSpread(null);
  self::nullAwareSetSpread(null);
  self::nullAwareMapSpread(null);
}