diff --git a/src/lib/container/intvector.go b/src/lib/container/intvector.go
index 9aae50d6eb5..775d3682c93 100644
--- a/src/lib/container/intvector.go
+++ b/src/lib/container/intvector.go
@@ -6,59 +6,74 @@ package vector
 
 import "vector"
 
+// IntVector is a specialization of Vector that hides the wrapping of Elements around ints.
 type IntVector struct {
 	// TODO do not export field
 	vector.Vector;
 }
 
 
+// Init initializes a new or resized vector.  The initial length may be <= 0 to
+// request a default length.  If initial_len is shorter than the current
+// length of the IntVector, trailing elements of the IntVector will be cleared.
 func (p *IntVector) Init(len int) *IntVector {
 	p.Vector.Init(len);
 	return p;
 }
 
 
+// NewIntVector returns an initialized new IntVector with length at least len.
 func NewIntVector(len int) *IntVector {
 	return new(IntVector).Init(len)
 }
 
 
+// At returns the i'th element of the vector.
 func (p *IntVector) At(i int) int {
 	return p.Vector.At(i).(int)
 }
 
 
+// Set sets the i'th element of the vector to value x.
 func (p *IntVector) Set(i int, x int) {
 	p.Vector.Set(i, x)
 }
 
 
+// Last returns the element in the vector of highest index.
 func (p *IntVector) Last() int {
 	return p.Vector.Last().(int)
 }
 
 
+// Insert inserts into the vector an element of value x before
+// the current element at index i.
 func (p *IntVector) Insert(i int, x int) {
 	p.Vector.Insert(i, x)
 }
 
 
+// Delete deletes the i'th element of the vector.  The gap is closed so the old
+// element at index i+1 has index i afterwards.
 func (p *IntVector) Delete(i int) int {
 	return p.Vector.Delete(i).(int)
 }
 
 
+// Push appends x to the end of the vector.
 func (p *IntVector) Push(x int) {
 	p.Vector.Push(x)
 }
 
 
+// Pop deletes and returns the last element of the vector.
 func (p *IntVector) Pop() int {
 	return p.Vector.Pop().(int)
 }
 
 
 // SortInterface support
+// Less returns a boolean denoting whether the i'th element is less than the j'th element.
 func (p *IntVector) Less(i, j int) bool {
 	return p.At(i) < p.At(j)
 }