the FlatArrayIterator has been moved to the new file iter-list.go

iter-list.go

@@ -0,0 +1,42 @@
+// Copyright (c) 2024 Celestino Amoroso (celestino.amoroso@gmail.com).
+// All rights reserved.
+
+// iter-list.go
+package expr
+
+import "io"
+
+type FlatArrayIterator struct {
+	a     []any
+	index int
+}
+
+func NewFlatArrayIterator(array []any) *FlatArrayIterator {
+	return &FlatArrayIterator{a: array, index: 0}
+}
+
+func (it *FlatArrayIterator) Current() (item any, err error) {
+	if it.index >= 0 && it.index < len(it.a) {
+		item = it.a[it.index]
+	} else {
+		err = io.EOF
+	}
+	return
+}
+
+func (it *FlatArrayIterator) Next() (item any, err error) {
+	if item, err = it.Current(); err != io.EOF {
+		it.index++
+	}
+	// if it.index < len(it.a) {
+	// 	item = it.a[it.index]
+	// 	it.index++
+	// } else {
+	// 	err = io.EOF
+	// }
+	return
+}
+
+func (it *FlatArrayIterator) Index() int {
+	return it.index - 1
+}

iterator.go

@@ -4,37 +4,8 @@
 // iterator.go
 package expr
 
-import "io"
-
 type Iterator interface {
-	Reset()
 	Next() (item any, err error) // must return io.EOF after the last item
+	Current() (item any, err error)
 	Index() int
 }
-
-type FlatArrayIterator struct {
-	a     []any
-	index int
-}
-
-func NewFlatArrayIterator(array []any) *FlatArrayIterator {
-	return &FlatArrayIterator{a: array, index: 0}
-}
-
-func (it *FlatArrayIterator) Reset() {
-	it.index = 0
-}
-
-func (it *FlatArrayIterator) Next() (item any, err error) {
-	if it.index < len(it.a) {
-		item = it.a[it.index]
-		it.index++
-	} else {
-		err = io.EOF
-	}
-	return
-}
-
-func (it *FlatArrayIterator) Index() int {
-	return it.index - 1
-}