| package strings | |
| func Replace(s, old, new string, n int) string | |
| func Index(haystack, needle string) int | |
| func Contains(haystack, needle string) bool | |
| func HasPrefix(s, prefix string) bool | |
| func EqualFold(s, t string) bool | |
| func ToLower(s string) string | |
| type Builder struct{} | |
| func (b *Builder) WriteString(s string) (int, error) | |
| func (b *Builder) String() string |