Remove specialized, unused iterator implementations

Signed-off-by: Christian Haudum <christian.haudum@gmail.com>

pkg/iter/v2/iter.go

@@ -159,75 +159,6 @@ func NewCancelableIter[T any](ctx context.Context, itr Iterator[T]) *Cancellable
 	return &CancellableIter[T]{ctx: ctx, Iterator: itr}
 }
 
-type IndexedValue[T any] struct {
-	idx int
-	val T
-}
-
-func (iv IndexedValue[T]) Value() T {
-	return iv.val
-}
-
-func (iv IndexedValue[T]) Index() int {
-	return iv.idx
-}
-
-type IterWithIndex[T any] struct {
-	Iterator[T]
-	zero  T // zero value of T
-	cache IndexedValue[T]
-}
-
-func (it *IterWithIndex[T]) At() IndexedValue[T] {
-	it.cache.val = it.Iterator.At()
-	return it.cache
-}
-
-func NewIterWithIndex[T any](iter Iterator[T], idx int) Iterator[IndexedValue[T]] {
-	return &IterWithIndex[T]{
-		Iterator: iter,
-		cache:    IndexedValue[T]{idx: idx},
-	}
-}
-
-type SliceIterWithIndex[T any] struct {
-	xs    []T // source slice
-	pos   int // position within the slice
-	zero  T   // zero value of T
-	cache IndexedValue[T]
-}
-
-func (it *SliceIterWithIndex[T]) Next() bool {
-	it.pos++
-	return it.pos < len(it.xs)
-}
-
-func (it *SliceIterWithIndex[T]) Err() error {
-	return nil
-}
-
-func (it *SliceIterWithIndex[T]) At() IndexedValue[T] {
-	it.cache.val = it.xs[it.pos]
-	return it.cache
-}
-
-func (it *SliceIterWithIndex[T]) Peek() (IndexedValue[T], bool) {
-	if it.pos+1 >= len(it.xs) {
-		it.cache.val = it.zero
-		return it.cache, false
-	}
-	it.cache.val = it.xs[it.pos+1]
-	return it.cache, true
-}
-
-func NewSliceIterWithIndex[T any](xs []T, idx int) PeekIterator[IndexedValue[T]] {
-	return &SliceIterWithIndex[T]{
-		xs:    xs,
-		pos:   -1,
-		cache: IndexedValue[T]{idx: idx},
-	}
-}
-
 func NewCloseableIterator[T io.Closer](itr Iterator[T]) *CloseIter[T] {
 	return &CloseIter[T]{itr}
 }

pkg/iter/v2/iter_test.go

@@ -6,35 +6,6 @@ import (
 	"github.com/stretchr/testify/require"
 )
 
-func TestSliceIterWithIndex(t *testing.T) {
-	t.Parallel()
-	t.Run("SliceIterWithIndex implements PeekingIterator interface", func(t *testing.T) {
-		xs := []string{"a", "b", "c"}
-		it := NewSliceIterWithIndex(xs, 123)
-
-		// peek at first item
-		p, ok := it.Peek()
-		require.True(t, ok)
-		require.Equal(t, "a", p.val)
-		require.Equal(t, 123, p.idx)
-
-		// proceed to first item
-		require.True(t, it.Next())
-		require.Equal(t, "a", it.At().val)
-		require.Equal(t, 123, it.At().idx)
-
-		// proceed to second and third item
-		require.True(t, it.Next())
-		require.True(t, it.Next())
-
-		// peek at non-existing fourth item
-		p, ok = it.Peek()
-		require.False(t, ok)
-		require.Equal(t, "", p.val) // "" is zero value for type string
-		require.Equal(t, 123, p.idx)
-	})
-}
-
 func TestPeekingIterator(t *testing.T) {
 	t.Parallel()
 	data := []int{1, 2, 3, 4, 5}