t.Fatalf("want %q, ErrBufFull got %q, err=%v", "abcdefghijklmnop", string(s), err)
	}
	if _, err := buf.Read(p[0:3]); string(p[0:3]) != "abc" || err != nil {
		t.Fatalf("want %q got %q, err=%v", "abc", string(p[0:3]), err)
	}
	if s, err := buf.Peek(1); string(s) != "d" || err != nil {
		t.Fatalf("want %q got %q, err=%v", "d", string(s), err)
	}

	B	foo(SB) // JMP foo(SB)
	BEQ	2(PC)
	B	bar<>(SB) // JMP bar<>(SB)

//
// BX
//
//	LTYPEBX comma ireg
//	{
//		outcode($1, Always, &nullgen, 0, &$3);
//	}
	BX	(R0)

//
// BEQ
//
//	LTYPE5 comma rel
//	{
//		outcode($1, Always, &nullgen, 0, &$3);
//	}
	BEQ	1(PC)

//
// SWI
//
//	LTYPE6 cond comma gen
//	{
//		outcode($1, $2, &nullgen, 0, &$4);
//	}
	SWI	$2
	SWI	$3

	in          string
	f           predicate
	first, last int
}

var indexFuncTests = []IndexFuncTest{
	{"", isValidRune, -1, -1},
	{"abc", isDigit, -1, -1},
	{"0123", isDigit, 0, 3},
	{"a1b", isDigit, 1, 1},
	{space, isSpace, 0, len(space) - 3}, // last rune in space is 3 bytes
	{"\u0e50\u0e5212hello34\u0e50\u0e51", isDigit, 0, 18},