From 8d44052b6dd9e27a5230f66239681cec601d3a8e Mon Sep 17 00:00:00 2001
From: Rob Pike <r@golang.org>
Date: Mon, 23 Mar 2009 17:46:59 -0700
Subject: [PATCH] iterator for vector

R=rsc
DELTA=35  (35 added, 0 deleted, 0 changed)
OCL=26662
CL=26662
---
 src/lib/container/vector.go      | 16 ++++++++++++++++
 src/lib/container/vector_test.go | 19 +++++++++++++++++++
 2 files changed, 35 insertions(+)

diff --git a/src/lib/container/vector.go b/src/lib/container/vector.go
index 9e738ebef4..673b47d021 100644
--- a/src/lib/container/vector.go
+++ b/src/lib/container/vector.go
@@ -210,3 +210,19 @@ func (p *Vector) Swap(i, j int) {
 	a := p.a;
 	a[i], a[j] = a[j], a[i]
 }
+
+
+// Iterate over all elements; driver for range
+func (p *Vector) iterate(c chan Element) {
+	for i := 0; i < len(p.a); i++ {
+		c <- p.a[i]
+	}
+	close(c);
+}
+
+// Channel iterator for range.
+func (p *Vector) Iter() chan Element {
+	c := make(chan Element);
+	go p.iterate(c);
+	return c;
+}
diff --git a/src/lib/container/vector_test.go b/src/lib/container/vector_test.go
index ac16709a0e..7a56f3664f 100644
--- a/src/lib/container/vector_test.go
+++ b/src/lib/container/vector_test.go
@@ -139,6 +139,7 @@ func TestInsertVector(t *testing.T) {
 	verify_pattern(t, a, 8, 1000, 2);
 }
 
+
 func TestSorting(t *testing.T) {
 	const n = 100;
 	a := vector.NewIntVector(n);
@@ -170,3 +171,21 @@ func TestDo(t *testing.T) {
 		t.Error("should visit", n, "values; did visit", count)
 	}
 }
+
+func TestIter(t *testing.T) {
+	const Len = 100;
+	x := vector.New(Len);
+	for i := 0; i < Len; i++ {
+		x.Set(i, i*i);
+	}
+	i := 0;
+	for v := range x.Iter() {
+		if v.(int) != i*i {
+			t.Error("Iter expected", i*i, "got", v.(int))
+		}
+		i++;
+	}
+	if i != Len {
+		t.Error("Iter stopped at", i, "not", Len)
+	}
+}
-- 
2.48.1