assert(validFontEncId(id));
assert(ComputerModernFamily::validFontEncId(id));
makeFontId(ComputerModernShaper::FontEncId id, MathVariant variant = NORMAL_VARIANT){  assert(validFontEncId(id));  assert(validMathVariant(variant));  return id | ((variant - NORMAL_VARIANT) << 4);}