string slicing is efficient so remove base and bounds arguments from RuneCountInString

R=rsc
DELTA=6  (1 added, 0 deleted, 5 changed)
OCL=28242
CL=28256

src/lib/strings.go

@@ -10,7 +10,7 @@ import "utf8"
 // Explode splits s into an array of UTF-8 sequences, one per Unicode character (still strings).
 // Invalid UTF-8 sequences become correct encodings of U+FFF8.
 func Explode(s string) []string {
-	a := make([]string, utf8.RuneCountInString(s, 0, len(s)));
+	a := make([]string, utf8.RuneCountInString(s));
 	j := 0;
 	var size, rune int;
 	for i := 0; i < len(a); i++ {
@@ -24,7 +24,7 @@ func Explode(s string) []string {
 // Count counts the number of non-overlapping instances of sep in s.
 func Count(s, sep string) int {
 	if sep == "" {
-		return utf8.RuneCountInString(s, 0, len(s))+1
+		return utf8.RuneCountInString(s)+1
 	}
 	c := sep[0];
 	n := 0;

src/lib/utf8.go

@@ -273,8 +273,9 @@ func RuneCount(p []byte) int {
 }
 
 // RuneCountInString is like RuneCount but its input is a string.
-func RuneCountInString(s string, i int, l int) int {
-	ei := i + l;
+func RuneCountInString(s string) int {
+	ei := len(s);
+	i := 0;
 	n := 0;
 	for n = 0; i < ei; n++ {
 		if s[i] < RuneSelf {

src/lib/utf8_test.go

@@ -169,7 +169,7 @@ var runecounttests = []RuneCountTest {
 func TestRuneCount(t *testing.T) {
 	for i := 0; i < len(runecounttests); i++ {
 		tt := runecounttests[i];
-		if out := utf8.RuneCountInString(tt.in, 0, len(tt.in)); out != tt.out {
+		if out := utf8.RuneCountInString(tt.in); out != tt.out {
 			t.Errorf("RuneCountInString(%q) = %d, want %d", tt.in, out, tt.out);
 		}
 		if out := utf8.RuneCount(bytes(tt.in)); out != tt.out {