JavaSript backend (early stage)

vlib/builtin/string.v

@@ -78,10 +78,9 @@ pub fn (s string) replace(rep, with string) string {
 	if s.len == 0 || rep.len == 0 {
 		return s
 	}
-	// println('"$s" replace  "$rep" with "$with" rep.len=$rep.len')
 	// TODO PERF Allocating ints is expensive. Should be a stack array
 	// Get locations of all reps within this string
-	mut idxs := []int{}
+	mut idxs := []int
 	mut rem := s
 	mut rstart := 0
 	for {
@@ -352,37 +351,58 @@ pub fn (s string) substr(start, end int) string {
 	return res
 }
 
-// KMP search
-pub fn (s string) index(p string) int {
+pub fn (s string) index_old(p string) int {
 	if p.len > s.len {
 		return -1
 	}
-	mut prefix := [0; p.len]
-	mut j := 0
-	for i := 1; i < p.len; i++ {
-		for p[j] != p[i] && j > 0 {
-			j = prefix[j - 1]
-		}
-		if p[j] == p[i] {
-			j++
-		}
-		prefix[i] = j
-	}
-	j = 0
-	for i := 0; i < s.len; i++ {
-		for p[j] != s[i] && j > 0 {
-			j = prefix[j - 1]
-		}
-		if p[j] == s[i] {
+	mut i := 0
+	for i < s.len {
+		mut j := 0
+		mut ii := i
+		for j < p.len && s[ii] == p[j] {
 			j++
+			ii++
 		}
 		if j == p.len {
 			return i - p.len + 1
 		}
+		i++
 	}
 	return -1
 }
 
+// KMP search
+pub fn (s string) index(p string) int {
+        if p.len > s.len {
+                return -1
+        }
+        mut prefix := [0].repeat2(p.len)
+        mut j := 0
+        for i := 1; i < p.len; i++ {
+                for p[j] != p[i] && j > 0 {
+                        j = prefix[j - 1]
+                }
+                if p[j] == p[i] {
+                        j++
+                }
+                prefix[i] = j
+        }
+        j = 0
+        for i := 0; i < s.len; i++ {
+                for p[j] != s[i] && j > 0 {
+                        j = prefix[j - 1]
+                }
+                if p[j] == s[i] {
+                        j++
+                }
+                if j == p.len {
+                        return i - p.len + 1
+                }
+        }
+        return -1
+}
+
+
 pub fn (s string) index_any(chars string) int {
 	for c in chars {
 		index := s.index(c.str())
@@ -874,7 +894,7 @@ pub fn (s string) bytes() []byte {
 	if s.len == 0 {
 		return []byte
 	}
-	mut buf := [byte(0); s.len]
+	mut buf := [byte(0)].repeat2(s.len)
 	C.memcpy(buf.data, s.str, s.len)
 	return buf
 }