================ @@ -0,0 +1,310 @@ +====================== +Clang-Change-Namespace +====================== + +.. contents:: + +.. toctree:: + :maxdepth: 1 + +:program:`clang-change-namespace` can be used to change the surrounding +namespaces of class/function definitions. + +Classes/functions in the moved namespace will have new namespaces while +references to symbols (e.g. types, functions) which are not defined in the +changed namespace will be correctly qualified by prepending namespace specifiers +before them. This will try to add shortest namespace specifiers possible. + +When a symbol reference needs to be fully-qualified, this adds a `::` prefix to +the namespace specifiers unless the new namespace is the global namespace. For +classes, only classes that are declared/defined in the given namespace in +specified files will be moved: forward declarations will remain in the old +namespace. The will be demonstrated in the next example. + +Example usage +------------- + +For example, consider this `test.cc` example here with the forward declared +class `FWD` and the defined class `A`, both in the namespace `a`. + +.. code-block:: c++ + + namespace a { + class FWD; + class A { + FWD *fwd; + }; + } // namespace a + +And now let's change the namespace `a` to `x`. + +.. code-block:: console + + clang-change-namespace \ + --old_namespace "a" \ + --new_namespace "x" \ + --file_pattern "test.cc" \ + --i \ + test.cc + +Note that in the code below there's still the forward decalred class `FWD` that +stayed in the namespace `a`. It wasn't moved to the new namespace because it +wasn't defined/declared here in `a` but only forward declared. + +.. code-block:: c++ + + namespace a { + class FWD; + } // namespace a + namespace x { + + class A { + a::FWD *fwd; + }; + } // namespace x + + +Another example +--------------- + +Consider this `test.cc` file: + +.. code-block:: c++ + + namespace na { + class X {}; + namespace nb { + class Y { + X x; + }; + } // namespace nb + } // namespace na + +To move the definition of class `Y` from namespace `na::nb` to `x::y`, run: + +.. code-block:: console + + clang-change-namespace \ + --old_namespace "na::nb" \ + --new_namespace "x::y" \ + --file_pattern "test.cc" \ + --i \ + test.cc + +This will overwrite `test.cc` to look like this: + +.. code-block:: c++ + + namespace na { + class X {}; + + } // namespace na + namespace x { + namespace y { + class Y { + na::X x; + }; + } // namespace y + } // namespace x + +Note, that we've successfully moved the class `Y` from namespace `na::nb` to +namespace `x::y`. + +Caveats +======= + +Content already exists in new namespace +--------------------------------------- + +Consider this `test.cc` example that defines two `class A` one inside the +namespace `a` and one in namespace `b`: + +.. code-block:: c++ + + namespace a { + class A { + int classAFromWithinNamespace_a; + }; + } // namespace a + + namespace b { + class A { + int classAFromWithinNamespace_b; + }; + } //namespace b + +Let's move everything from the namespace `a` to the global namespace +(`--new_namespace ""` means global namespace): ---------------- kwk wrote:
You are correct. I wrote this and then jumped to adding the documentation to the parameter instead. Fixed in 30bf1f851af7dea31985645e66c41f356589dfa7. https://github.com/llvm/llvm-project/pull/148277 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits