/* move existing text out of the way, insert new text, and update cursor */
memmove(&text[cursor + n], &text[cursor], sizeof text - cursor - MAX(n, 0));
if (n > 0)
memcpy(&text[cursor], str, n);
cursor += n;
match();
/* move existing text out of the way, insert new text, and update cursor */
memmove(&text[cursor + n], &text[cursor], sizeof text - cursor - MAX(n, 0));
if (n > 0)
memcpy(&text[cursor], str, n);
cursor += n;
match();