Check that every magnitude fits in its target type #211
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`get_value<T>(m)` converts a magnitude `m` to its representation in type `T`. It produces a hard compiler error if the value can't fit. Its relative `get_value_result<T>(m)` always returns a result, but produces an error code if the value can't be represented. Previously, there was a hole in this system. We assumed that each magnitude could be represented in `std::uintmax_t`. Of course, if it couldn't, `get_value` would fail to compile as it should. But `get_value_result` would _also_ fail to compile, instead of producing an error condition. To fix this, we need to move our checking utilities further up in the file, so that all of our utilities can use them. `product`, `int_pow`, `base_power_value` --- they all need to _check their computations_ at every step. When we do this, we're able to gracefully detect the non-representability of huge numbers even for the biggest types.
chiphogg
added
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release notes: 🐛 lib (bugfix)
geoffviola
approved these changes
Dec 15, 2023
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get_value<T>(m)converts a magnitudemto its representation in typeT. It produces a hard compiler error if the value can't fit. Itsrelative
get_value_result<T>(m)always returns a result, but producesan error code if the value can't be represented.
Previously, there was a hole in this system. We assumed that each
magnitude could be represented in
std::uintmax_t. Of course, if itcouldn't,
get_valuewould fail to compile as it should. Butget_value_resultwould also fail to compile, instead of producing anerror condition.
To fix this, we need to move our checking utilities further up in the
file, so that all of our utilities can use them.
product,int_pow,base_power_value--- they all need to check their computations atevery step. When we do this, we're able to gracefully detect the
non-representability of huge numbers even for the biggest types.