But I expected to be able to do that simple task easily in pd
But Pd isn't really a general purpose programming environment, is it?
Its tolerances seem designed to be good enough for typical DSP tasks but even there, e.g., random access within an audio buffer longer than a few minutes is not really within reach of 32-bit Pd. (The tolerances are ok for oscillators and filters, or triggering short samples while arbitrarily long samples require disk streaming or some intricate tap dancing.)
SC does a better job of pretending to be a general purpose language. It isn't, not really, but it does have more goodies like local stack frames for function calls, a full complement of data structures, error handling (though with one outstanding bug), etc... leading to a funny question on the forum asking if SC has a native SMTP library for sending email... well, we don't have that kind of networking layer so, no. I guess user expectations exceed reality everywhere.
The punchline about floating point representation is that comments are parsed in the same way that object or message boxes are (or, comments used to be, I didn't check in the most recent Pd). Writing eg 10100111 would be truncated to scientific notation.