1 files changed, 66 insertions, 0 deletions
diff --git a/lib/bitset.cpp b/lib/bitset.cpp
new file mode 100644
index 0000000..bbd802d
--- /dev/null
+++ b/lib/bitset.cpp
@@ -0,0 +1,66 @@
+#include "bitset.h"
+
+namespace MyGrate {
+	static_assert(std::forward_iterator<BitSet::Iterator>);
+
+	BitSet::Iterator::Iterator(const std::byte * bb) : b {bb} { }
+
+	bool
+	BitSet::Iterator::operator*() const
+	{
+		return (*b & m) != std::byte {};
+	}
+
+	bool
+	BitSet::Iterator::operator==(const BitSet::Iterator & o) const
+	{
+		return b == o.b && m == o.m;
+	}
+
+	bool
+	BitSet::Iterator::operator!=(const BitSet::Iterator & o) const
+	{
+		return b != o.b || m != o.m;
+	}
+
+	BitSet::Iterator &
+	BitSet::Iterator::operator++()
+	{
+		if (m == std::byte {128}) {
+			b++;
+			m = std::byte {1};
+		}
+		else {
+			m <<= 1;
+		}
+		return *this;
+	}
+
+	BitSet::Iterator
+	BitSet::Iterator::operator++(int)
+	{
+		auto pre {*this};
+		++*this;
+		return pre;
+	}
+
+	BitSet::BitSet(const std::span<const std::byte> bs) : bytes {bs} { }
+
+	std::size_t
+	BitSet::size() const
+	{
+		return bytes.size() * 8;
+	}
+
+	BitSet::Iterator
+	BitSet::begin() const
+	{
+		return BitSet::Iterator {bytes.data()};
+	}
+
+	BitSet::Iterator
+	BitSet::end() const
+	{
+		return BitSet::Iterator {bytes.data() + bytes.size()};
+	}
+}