// It additionally reports whether caseRange contained a mapping for r.
func to(_case int, r rune, caseRange []CaseRange) (mappedRune rune, foundMapping bool) {
	if _case < 0 || MaxCase <= _case {
		return ReplacementChar, false // as reasonable an error as any
	}
	// binary search over ranges
	lo := 0
	hi := len(caseRange)
	for lo < hi {
		m := int(uint(lo+hi) >> 1)
		cr := caseRange[m]

// development first.

package unicode

var TurkishCase SpecialCase = _TurkishCase
var _TurkishCase = SpecialCase{
	CaseRange{0x0049, 0x0049, d{0, 0x131 - 0x49, 0}},
	CaseRange{0x0069, 0x0069, d{0x130 - 0x69, 0, 0x130 - 0x69}},
	CaseRange{0x0130, 0x0130, d{0, 0x69 - 0x130, 0}},
	CaseRange{0x0131, 0x0131, d{0x49 - 0x131, 0, 0x49 - 0x131}},
}

}

func TestSpecialCaseNoMapping(t *testing.T) {
	// Issue 25636
	// no change for rune 'A', zero delta, under upper/lower/title case change.
	var noChangeForCapitalA = CaseRange{'A', 'A', [MaxCase]rune{0, 0, 0}}
	got := strings.ToLowerSpecial(SpecialCase([]CaseRange{noChangeForCapitalA}), "ABC")
	want := "Abc"
	if got != want {
		t.Errorf("got %q; want %q", got, want)
	}
}

func TestNegativeRune(t *testing.T) {

var Adlam <type 1>;
var Ahom <type 1>;
var Anatolian_Hieroglyphs <type 1>;
var Arabic <type 1>;
var Armenian <type 1>;
var Avestan <type 1>;
var AzeriCase <type 10 "SpecialCase" <type 11 [] <type 12 "CaseRange" <type 13 struct { Lo <type -7>; Hi <type -7>; Delta <type 14 ".unicode.d" <type 15 [3 ] <type -21>>>; }>>>
 func (special <type 10>) ToUpper (r <type -21>) <type -21>;
 func (special <type 10>) ToTitle (r <type -21>) <type -21>;

		{"Buginese", Var, 0},
		{"Buhid", Var, 0},
		{"C", Var, 0},
		{"Canadian_Aboriginal", Var, 0},
		{"Carian", Var, 0},
		{"CaseRange", Type, 0},
		{"CaseRange.Delta", Field, 0},
		{"CaseRange.Hi", Field, 0},
		{"CaseRange.Lo", Field, 0},
		{"CaseRanges", Var, 0},
		{"Categories", Var, 0},
		{"Caucasian_Albanian", Var, 4},
		{"Cc", Var, 0},
		{"Cf", Var, 0},
		{"Chakma", Var, 1},

)

// CaseRanges is the table describing case mappings for all letters with
// non-self mappings.
var CaseRanges = _CaseRanges
var _CaseRanges = []CaseRange{
	{0x0041, 0x005A, d{0, 32, 0}},
	{0x0061, 0x007A, d{-32, 0, -32}},
	{0x00B5, 0x00B5, d{743, 0, 743}},
	{0x00C0, 0x00D6, d{0, 32, 0}},

pkg unicode, method (SpecialCase) ToTitle(int32) int32
pkg unicode, method (SpecialCase) ToUpper(int32) int32
pkg unicode, type CaseRange struct
pkg unicode, type CaseRange struct, Delta d
pkg unicode, type CaseRange struct, Hi uint32
pkg unicode, type CaseRange struct, Lo uint32
pkg unicode, type Range16 struct
pkg unicode, type Range16 struct, Hi uint16
pkg unicode, type Range16 struct, Lo uint16