{_Literal, "'\\U0000ff16'", 0, 0},
	{_Literal, "`foobar`", 0, 0},
	{_Literal, "`foo\tbar`", 0, 0},
	{_Literal, "`\r`", 0, 0},

	// operators
	{_Operator, "!", Not, 0},
	{_Operator, "~", Tilde, 0},

	{_Operator, "||", OrOr, precOrOr},

	{_Operator, "&&", AndAnd, precAndAnd},

	{_Operator, "==", Eql, precCmp},
	{_Operator, "!=", Neq, precCmp},
	{_Operator, "<", Lss, precCmp},

		{"!\"#$%&'()*+,-.／:;<=>?@[\\]^_`{|}~", true},
		{"␀␁␂␃␄␅␆␇␈␉␊␋␌␍␎␏␐␑␒␓␔␕␖␗␘␙␚␛␜␝␞␟␡", true},
		{"trailing VT␋/trailing VT␋", true},
		{"␋leading VT/␋leading VT", true},
		{"~leading tilde", true},
		{"\rleading CR", true},
		{"\nleading LF", true},
		{"\tleading HT", true},
		{"trailing CR\r", true},
		{"trailing LF\n", true},
		{"trailing HT\t", true},
		// cases for which test should fail.

        entities.put("Scaron", "\u0160");
        entities.put("scaron", "\u0161");
        entities.put("Yuml", "\u0178");
        entities.put("circ", "\u02c6");
        entities.put("tilde", "\u02dc");
        entities.put("ensp", "\u2002");
        entities.put("emsp", "\u2003");
        entities.put("thinsp", "\u2009");
        entities.put("zwnj", "\u200c");
        entities.put("zwj", "\u200d");

		var terms []*Term
		if !tp.is(func(t *term) bool {
			if t == nil {
				return false
			}
			if r := f(t.typ); r != nil {
				terms = append(terms, NewTerm(t.tilde, r))
				return true
			}
			return false
		}) {
			return nil
		}

		// We can type-check this fine but we're introducing a synthetic
		// type parameter for the result. It's not clear what the API

	// embed it in an implicit interface so that only interface type-checking
	// needs to take care of such type expressions.
	if op, _ := x.(*syntax.Operation); op != nil && (op.Op == syntax.Tilde || op.Op == syntax.Or) {
		t := check.typ(&syntax.InterfaceType{MethodList: []*syntax.Field{{Type: x}}})
		// mark t as implicit interface if all went well
		if t, _ := t.(*Interface); t != nil {
			t.implicit = true
		}

			} else {
				tok = s.switch3(token.AND, token.AND_ASSIGN, '&', token.LAND)
			}
		case '|':
			tok = s.switch3(token.OR, token.OR_ASSIGN, '|', token.LOR)
		case '~':
			tok = token.TILDE
		default:
			// next reports unexpected BOMs - don't repeat
			if ch != bom {
				// Report an informative error for U+201[CD] quotation
				// marks, which are easily introduced via copy and paste.

	{token.PERIOD, ".", operator},

	{token.RPAREN, ")", operator},
	{token.RBRACK, "]", operator},
	{token.RBRACE, "}", operator},
	{token.SEMICOLON, ";", operator},
	{token.COLON, ":", operator},
	{token.TILDE, "~", operator},

	// Keywords
	{token.BREAK, "break", keyword},
	{token.CASE, "case", keyword},
	{token.CHAN, "chan", keyword},
	{token.CONST, "const", keyword},
	{token.CONTINUE, "continue", keyword},

		var terms []*Term
		if !tp.is(func(t *term) bool {
			if t == nil {
				return false
			}
			if r := f(t.typ); r != nil {
				terms = append(terms, NewTerm(t.tilde, r))
				return true
			}
			return false
		}) {
			return nil
		}

		// We can type-check this fine but we're introducing a synthetic
		// type parameter for the result. It's not clear what the API

        entities.put("Scaron", "\u0160");
        entities.put("scaron", "\u0161");
        entities.put("Yuml", "\u0178");
        entities.put("circ", "\u02c6");
        entities.put("tilde", "\u02dc");
        entities.put("ensp", "\u2002");
        entities.put("emsp", "\u2003");
        entities.put("thinsp", "\u2009");
        entities.put("zwnj", "\u200c");
        entities.put("zwj", "\u200d");

	// embed it in an implicit interface so that only interface type-checking
	// needs to take care of such type expressions.
	wrap := false
	switch op := x.(type) {
	case *ast.UnaryExpr:
		wrap = op.Op == token.TILDE
	case *ast.BinaryExpr:
		wrap = op.Op == token.OR
	}
	if wrap {
		x = &ast.InterfaceType{Methods: &ast.FieldList{List: []*ast.Field{{Type: x}}}}
		t := check.typ(x)