`tom_som_cpp_v0` — runnable samples

Three runnable samples covering the three access paths to a TomSpecs Spec Object Model document (som_multiplatform_spec_model.md §6). They are hand-authored and preserved across generate_som regeneration (the generator only rewrites the header/source pair (include/, src/), meta/, schemas/ and the Makefile).

Each sample is a single .cpp file. Every sample reaches the generic runtime purely through the include path (-I$(RUNTIME_DIR)/include), wired by the Makefile's relative RUNTIME_DIR, so the samples are portable across checkouts.

Build & run

From the project root, the runner builds both static libraries and then compiles + runs the behavioural test and all three samples:

./run_tests.sh

To compile a single sample directly (after make and make -C ../tom_som_cpp_runtime):

g++ -std=c++17 -Iinclude -I../tom_som_cpp_runtime/include \
   examples/a_typed_access.cpp \
   build/libtom_som_cpp_v0.a ../tom_som_cpp_runtime/build/libtom_som_cpp_runtime.a \
   -o build/a_typed_access
./build/a_typed_access

Sample (c) reads meta/spec_model.meta.json relative to the current directory, so run it from the project root (or pass an explicit path as its first argument).

Sample	File	Access path
(a) Typed object-model	a_typed_access.cpp	The generated typed facade — named accessor member functions, nested-section navigation, the path-based som::SomList collection.
(b) Generic document	b_generic_document.cpp	The language-independent generic runtime — string paths into a sparse store, plus JSON / YAML serialization.
(c) Reflection / meta-data	c_reflection_metadata.cpp	The value-free reflection surface — load meta/spec_model.meta.json into a som::SpecModel , enumerate roots/fields, resolve paths to model nodes.

All three describe the same document shape, and produce output equivalent to their Dart/Python/Java/JavaScript/TypeScript/Go/Rust/C counterparts in tom_som_dart_v0/example/, tom_som_python_v0/examples/, tom_som_java_v0/examples/, tom_som_javascript_v0/examples/, tom_som_typescript_v0/examples/, tom_som_go_v0/examples/, tom_som_rust_v0/examples/ and tom_som_c_v0/examples/ — illustrating that the typed facade (a) is a thin editing surface over the exact generic store (b), whose schema is described by the reflection model (c).

Ownership notes (C++-specific, RAII)

• The som::SpecDocument is a value (som::SpecDocument doc;). It is

borrowed by every facade bound to it (each holds a SpecDocument&) and must outlive them — declare it before, and in an outer scope to, its facades. - Facade nodes are values: copy/move them freely; there is nothing to free. - Typed getters return std::string by value. - som::SomList::add() returns the new item's path; element facades are constructed from it (Elem item(doc, path)). - The serialization helpers (SpecDocument::toJson() → som::documentJsonToCanonicalJson, som::encodeYaml) return owned values. - som::SpecModel::fromJsonStr returns a std::unique_ptr<SpecModel>; reflection results borrow from the model, so keep the model alive.