p, _ := Compile(re)
		s := p.String()
		if s != tt.Prog {
			t.Errorf("compiled %#q:\n--- have\n%s---\n--- want\n%s---", tt.Regexp, s, tt.Prog)
		}
	}
}

func BenchmarkEmptyOpContext(b *testing.B) {
	for i := 0; i < b.N; i++ {
		var r1 rune = -1
		for _, r2 := range "foo, bar, baz\nsome input text.\n" {
			EmptyOpContext(r1, r2)
			r1 = r2
		}
		EmptyOpContext(r1, -1)
	}
}