indexed_bitset¶
indexed_bitset is to std::bitset what indexed_array is to
std::array: it offers similar features, but uses a custom indexing
scheme to access individual bits instead of a standard 0-based index.
It only offers a subset of std::bitset interface, because some
features may be counter-intuitive and as such dangerous. If you need
these features, you can explicitly cast an indexed_bitset to its
underlying std::bitset.
Usage¶
Declaring an indexed_bitset follows the same pattern as
indexed_array, but there is no value type: it is always a bool:
indexed_bitset<index_range<1, 10>> b(0b1001001001u);
assert(b.size() == 10);
Operations available¶
The common operations on bitset are available:
// construct from unsigned value
test
set
reset
flip
operator[]
size
to_ulong
to_ullong
and additionally in_range to check if a value is in the range of acceptable
values for the indexer. Notably, assignment operators are disabled,
because they are too error prone. If assignment is needed, first cast it to
the underlying std::bitset:
indexed_bitset<index_range<1, 10>> b(0u);
static_cast<std::bitset&>(b) = 0x08u;
assert(b[4].test()); // 1-based indexing !