// Copyright 2023 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

// Package iter provides basic definitions and operations
// related to iteration in Go.
package iter

import (
	"internal/race"
	"runtime"
	"unsafe"
)

// Seq is an iterator over sequences of individual values.

	var wg sync.WaitGroup
	var iterChans [2]chan intIter
	wg.Add(2)
	iterChans[0] = make(chan intIter)
	iterChans[1] = make(chan intIter)
	go func() {
		defer wg.Done()

		iter := pullRange(100)
		iterChans[1] <- iter

		for i := range iterChans[0] {
			_, ok := i.next()
			if !ok {
				close(iterChans[1])
				break
			}
			iterChans[1] <- i
		}
	}()
	go func() {
		defer wg.Done()

### Iterators

The new [iter] package provides the basic definitions for working with
user-defined iterators.

The [slices] package adds several functions that work with iterators:
- [All](/pkg/slices#All) returns an iterator over slice indexes and values.
- [Values](/pkg/slices#Values) returns an iterator over slice elements.
- [Backward](/pkg/slices#Backward) returns an iterator that loops over
  a slice backward.

    Enumeration<Integer> enumer = enumerate(1, 2, 3);
    Iterator<Integer> iter = Iterators.forEnumeration(enumer);

    assertTrue(iter.hasNext());
    assertEquals(1, (int) iter.next());
    assertTrue(iter.hasNext());
    assertEquals(2, (int) iter.next());
    assertTrue(iter.hasNext());
    assertEquals(3, (int) iter.next());
    assertFalse(iter.hasNext());
  }

  public void testAsEnumerationEmpty() {

    def post_root(item1: Item, item2: Item):
        return item1, item2  # pragma: nocover

    @router.post(
        "/router", response_model=List[Item], responses={404: {"model": List[Message]}}
    )
    def post_router(item1: Item, item2: Item):
        return item1, item2  # pragma: nocover

    app.include_router(router)
    client = TestClient(app)

                    def workQueue2 = submit(ParallelWorkAction.class, [ "item3" ])

                    signal("submitted")

                    workQueue1.await()

                    signal("finished")
                }
            }
        """

        def started = blockingHttpServer.expectConcurrentAndBlock("item1", "item2", "item3", "submitted")

	// (sometimes it takes 1 time, sometimes it takes ~4,000+).
	for iter := 0; ; iter++ {
		if iter%50 == 0 {
			fmt.Println(iter) // ERROR "iter escapes to heap$" "... argument does not escape$"
		}
		test1(iter)
		test2(iter)
		test3(iter)
		test4(iter)
		test5(iter)
		test6(iter)
	}
}

func test1(iter int) {

	const maxI = 500

          }
        };

    assertTrue(iter.hasNext());
    assertEquals(0, (int) iter.next());

    // verify idempotence of hasNext()
    assertTrue(iter.hasNext());
    assertTrue(iter.hasNext());
    assertTrue(iter.hasNext());
    assertEquals(1, (int) iter.next());

    assertFalse(iter.hasNext());

    // Make sure computeNext() doesn't get invoked again
    assertFalse(iter.hasNext());

    try {

	done.Add(4 * procs)
	for p := 0; p < procs; p++ {
		const iters = 1e3
		go func() {
			trace.WithRegion(context.Background(), "special", func() {
				for i := 0; i < iters; i++ {
					runtime.Gosched()
					c0 <- 0
				}
				done.Done()
			})
		}()
		go func() {
			trace.WithRegion(context.Background(), "special", func() {
				for i := 0; i < iters; i++ {
					runtime.Gosched()
					<-c0
				}
				done.Done()

                }
            }
        }

        iter = source.getAST().getStaticImports().values().iterator();
        while (iter.hasNext()) {
            ImportNode importedClass = iter.next();
            if (!AstUtils.isVisible(source, importedClass.getClassName())) {
                iter.remove();
            }
        }

        iter = source.getAST().getStaticStarImports().values().iterator();