import (
	"text/scanner"

	"cmd/internal/src"
)

// A Stack is a stack of TokenReaders. As the top TokenReader hits EOF,
// it resumes reading the next one down.
type Stack struct {
	tr []TokenReader
}

// Push adds tr to the top (end) of the input stack. (Popping happens automatically.)
func (s *Stack) Push(tr TokenReader) {
	s.tr = append(s.tr, tr)
}

func (s *Stack) Next() ScanToken {
	tos := s.tr[len(s.tr)-1]

  public final void addTearDown(TearDown tearDown) {
    synchronized (stack) {
      stack.addFirst(checkNotNull(tearDown));
    }
  }

  /** Causes teardown to execute. */
  public final void runTearDown() {
    List<Throwable> exceptions = new ArrayList<>();
    List<TearDown> stackCopy;
    synchronized (stack) {
      stackCopy = Lists.newArrayList(stack);
      stack.clear();
    }
    for (TearDown tearDown : stackCopy) {

	"cmd/asm/internal/flags"
	"cmd/internal/objabi"
	"cmd/internal/src"
)

// Input is the main input: a stack of readers and some macro definitions.
// It also handles #include processing (by pushing onto the input stack)
// and parses and instantiates macro definitions.
type Input struct {
	Stack
	includes        []string
	beginningOfLine bool
	ifdefStack      []bool
	macros          map[string]*Macro

    }

    return builder.buildOrThrow();
  }

  /**
   * Parses a trie node and returns the number of characters consumed.
   *
   * @param stack The prefixes that precede the characters represented by this node. Each entry of
   *     the stack is in reverse order.
   * @param encoded The serialized trie.
   * @param start An index in the encoded serialized trie to begin reading characters from.

	"signal.signal_recv",
	"sigterm.handler",
	"runtime_mcall",
	"goroutine in C code",
}

// Identify whether the stack trace entry is part of ignoredStackFn .
func isIgnoredStackFn(stack string) (ok bool) {
	ok = true
	for _, stackFn := range ignoredStackFns {
		if !strings.Contains(stack, stackFn) {
			ok = false
			continue
		}
		break
	}
	return ok
}

class DocBookBuilder {
    final LinkedList<Element> stack = new LinkedList<Element>();
    final Document document;

    DocBookBuilder(Document document) {
        this.document = document;
        stack.addFirst(document.createElement("root"));
    }

    List<Element> getElements() {
        List<Element> elements = new ArrayList<Element>();

    private final Deque<Iterator<T>> stack;

    PreOrderIterator(T root) {
      this.stack = new ArrayDeque<>();
      stack.addLast(Iterators.singletonIterator(checkNotNull(root)));
    }

    @Override
    public boolean hasNext() {
      return !stack.isEmpty();
    }

    @Override
    public T next() {
      Iterator<T> itr = stack.getLast(); // throws NSEE if empty

      } while (!UNSAFE.compareAndSwapObject(this, HEAD_OFFSET, stack, null));

      RunnableExecutorPair reversedStack = null;
      while (stack != NULL_PAIR) {
        RunnableExecutorPair head = stack;
        stack = stack.next;
        head.next = reversedStack;
        reversedStack = head;
      }
      stack = reversedStack;
      while (stack != null) {
        stack.execute();
        stack = stack.next;
      }

import okio.Buffer
import okio.BufferedSink
import okio.ByteString

internal class DerWriter(sink: BufferedSink) {
  /** A stack of buffers that will be concatenated once we know the length of each. */
  private val stack = mutableListOf(sink)

  /** Type hints scoped to the call stack, manipulated with [pushTypeHint] and [popTypeHint]. */
  private val typeHintStack = mutableListOf<Any?>()

  /**

                stack += superType to superClassSymbol
                if (superClassSymbol == superSymbol) {
                    result = stack.toList()
                    check(stack.removeLast().second == superClassSymbol)
                    break
                }
                dfs(superClassSymbol)
                check(stack.removeLast().second == superClassSymbol)
            }
        }