1b3642de4b
When a protocol supports multiple version some compile-time
optimizations become impossible. For example protocol transcoding always
has to check version at runtime and perform fast pass-through only when
version of source and target are the same. Consequently both code paths,
fast pass-through and field-by-field transcoding, must be instantiated,
increasing build time and size of the executable code.
This change defines a global protocol trait that can be specialized by an
application to fix the version of a protocol. Effectively application can
promise to use only one version of the protocol (defined by
bond::default_version<Reader>). For example in order to use only the
version 2 of Compact Binary protocol application could include a header
file in the generated code using --header option:
gbc c++ --header="<compact_binary_v2.h>" foo.bond
where compact_binary_v2.h contains:
#include <bond/core/traits.h>
#include <bond/core/bond_version.h>
namespace bond
{
template <typename Input>
class CompactBinaryReader;
template <typename Input> struct
default_version<CompactBinaryReader<Input> >
{
static const uint16_t value = v2;
};
template <typename Input> struct
enable_protocol_versions<CompactBinaryReader<Input> >
: false_type {};
}
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| inc/bond | ||
| test | ||
| .gitignore | ||
| CMakeLists.txt | ||