The to_json_string utility implementation was based on const references
instead of views, which can be a source of unnecessary memory copying.
This patch migrates all to_json_string to use bytes_view and leaves
the const reference version as a thin wrapper.
Message-Id: <2bf9f1951b862f8e8a2211cb4e83852e7ac70c67.1559654014.git.sarna@scylladb.com>
Both cql3_type and abstract_type are normally used inside
shared_ptr. This creates a problem when an abstract_type needs to refer
to a cql3_type as that creates a cycle.
To avoid warnings from asan, we were using a std::unordered_map to
store one of the edges of the cycle. This avoids the warning, but
wastes even more memory.
Even before this patch cql3_type was a fairly light weight
structure. This patch pushes in that direction and now cql3_type is a
struct with a single member variable, a data_type.
This avoids the reference cycle and is easier to understand IMHO.
Tests: unit (dev)
Signed-off-by: Rafael Ávila de Espíndola <espindola@scylladb.com>
