root/ROOT/RFieldUtils.hxx

0001 /// \file RFieldUtils.hxx
0002 /// \ingroup NTuple
0003 /// \author Jonas Hahnfeld <jonas.hahnfeld@cern.ch>
0004 /// \date 2024-11-19
0005
0006 #ifndef ROOT_RFieldUtils
0007 #define ROOT_RFieldUtils
0008
0009 #include <string>
0010 #include <string_view>
0011 #include <typeinfo>
0012 #include <tuple>
0013 #include <vector>
0014
0015 class TClass;
0016
0017 namespace ROOT {
0018 namespace Internal {
0019
0020 /// Applies RNTuple specific type name normalization rules (see specs) that help the string parsing in
0021 /// RFieldBase::Create(). The normalization of templated types does not include full normalization of the
0022 /// template arguments (hence "Prefix").
0023 std::string GetCanonicalTypePrefix(const std::string &typeName);
0024
0025 /// Given a type name normalized by ROOT meta, renormalize it for RNTuple. E.g., insert std::prefix.
0026 std::string GetRenormalizedTypeName(const std::string &metaNormalizedName);
0027
0028 /// Given a type info ask ROOT meta to demangle it, then renormalize the resulting type name for RNTuple. Useful to
0029 /// ensure that e.g. fundamental types are normalized to the type used by RNTuple (e.g. int -> std::int32_t).
0030 std::string GetRenormalizedDemangledTypeName(const std::type_info &ti);
0031
0032 /// Applies all RNTuple type normalization rules except typedef resolution.
0033 std::string GetNormalizedUnresolvedTypeName(const std::string &origName);
0034
0035 /// Appends 'll' or 'ull' to the where necessary and strips the suffix if not needed.
0036 std::string GetNormalizedInteger(const std::string &intTemplateArg);
0037 std::string GetNormalizedInteger(long long val);
0038 std::string GetNormalizedInteger(unsigned long long val);
0039 long long ParseIntTypeToken(const std::string &intToken);
0040 unsigned long long ParseUIntTypeToken(const std::string &uintToken);
0041
0042 /// Possible settings for the "rntuple.streamerMode" class attribute in the dictionary.
0043 enum class ERNTupleSerializationMode {
0044    kForceNativeMode,
0045    kForceStreamerMode,
0046    kUnset
0047 };
0048
0049 ERNTupleSerializationMode GetRNTupleSerializationMode(TClass *cl);
0050
0051 /// Parse a type name of the form `T[n][m]...` and return the base type `T` and a vector that contains,
0052 /// in order, the declared size for each dimension, e.g. for `unsigned char[1][2][3]` it returns the tuple
0053 /// `{"unsigned char", {1, 2, 3}}`. Extra whitespace in `typeName` should be removed before calling this function.
0054 ///
0055 /// If `typeName` is not an array type, it returns a tuple `{T, {}}`. On error, it returns a default-constructed tuple.
0056 std::tuple<std::string, std::vector<std::size_t>> ParseArrayType(const std::string &typeName);
0057
0058 /// Used in RFieldBase::Create() in order to get the comma-separated list of template types
0059 /// E.g., gets {"int", "std::variant<double,int>"} from "int,std::variant<double,int>".
0060 /// TODO(jblomer): Try to merge with TClassEdit::TSplitType
0061 std::vector<std::string> TokenizeTypeList(std::string_view templateType);
0062
0063 } // namespace Internal
0064 } // namespace ROOT
0065
0066 #endif