kubernetes/vendor/golang.org/x/net/http2/ascii.go

// asciiEqualFold is strings.EqualFold, ASCII only. It reports whether s and t
// are equal, ASCII-case-insensitively.
func asciiEqualFold(s, t string) bool { … }

// lower returns the ASCII lowercase version of b.
func lower(b byte) byte { … }

// isASCIIPrint returns whether s is ASCII and printable according to
// https://tools.ietf.org/html/rfc20#section-4.2.
func isASCIIPrint(s string) bool { … }

// asciiToLower returns the lowercase version of s if s is ASCII and printable,
// and whether or not it was.
func asciiToLower(s string) (lower string, ok bool) { … }