[perf] Remove memory copy when using string delimiter

src/util/chars.go

@@ -118,3 +118,39 @@ func (chars *Chars) Slice(b int, e int) Chars {
 	}
 	return Chars{bytes: chars.bytes[b:e]}
 }
+
+func (chars *Chars) Split(delimiter string) []Chars {
+	delim := []rune(delimiter)
+	numChars := chars.Length()
+	numDelim := len(delim)
+	begin := 0
+	ret := make([]Chars, 0, 1)
+
+	for index := 0; index < numChars; {
+		if index+numDelim <= numChars {
+			match := true
+			for off, d := range delim {
+				if chars.Get(index+off) != d {
+					match = false
+					break
+				}
+			}
+			// Found the delimiter
+			if match {
+				incr := Max(numDelim, 1)
+				ret = append(ret, chars.Slice(begin, index+incr))
+				index += incr
+				begin = index
+				continue
+			}
+		} else {
+			// Impossible to find the delimiter in the remaining substring
+			break
+		}
+		index++
+	}
+	if begin < numChars || len(ret) == 0 {
+		ret = append(ret, chars.Slice(begin, numChars))
+	}
+	return ret
+}