Add openAsChild, currently without writing support

1 files changed, 10 insertions, 1 deletions

diff --git a/src/cppc4group.hpp b/src/cppc4group.hpp
index a1bb28a..c30af44 100644
--- a/src/cppc4group.hpp
+++ b/src/cppc4group.hpp
@@ -5,7 +5,7 @@
 // although, when dealing with raw memory (because cc4group can't know the type of the stored data) also users of this wrapper have to deal with some void*
 // because most methods behave exactly the same, please look at cc4group.h for their description (they are named exactly the same with a few exceptions)
 // in case their are real differences, they will be noted in this header also
-// until now, all examples only use cc4group's C-API, but as a C++-programmer you should have no problems reading them anyway
+// until now, all except one example only use cc4group's C-API, but as a C++-programmer you should have no problems reading them anyway
 // one general difference to the C-API that is not mentioned at the individual methods is that functions actually returning data return an std::optional instead of a bool...
 // ...the optional will be populated normally and empty in error cases
 
@@ -22,6 +22,9 @@ class CppC4Group {
 
 	std::unique_ptr<Private> p;
 
+	// this is only needed for internal purposes
+	CppC4Group(std::unique_ptr<Private>&& p);
+
 public:
 	// this struct is used for the getEntryData-method to return them in a uniform way (instead of using reference- or pointer-arguments)
 	struct Data {
@@ -100,6 +103,9 @@ public:
 	// the constructor will automatically construct an internal CC4Group, so no new-equivalent method is needed
 	CppC4Group();
 
+	// the move constructor is needed to move the returned group out of the optional from openAsChild
+	CppC4Group(CppC4Group&& other);
+
 	// the destructor will automatically delete the internal CC4Group, so also no extra method needed
 	~CppC4Group();
 
@@ -138,4 +144,7 @@ public:
 	bool createFile(const std::string& path);
 
 	bool setEntryData(const std::string& path, const void* const data = nullptr, const size_t size = 0, const MemoryManagement management = Copy);
+
+	// to get the child group out of the optional in case of success, construct a new CppC4Group with the move constructor: CppC4Group child{std::move(*optionalChild)};
+	std::optional<CppC4Group> openAsChild(const std::string& path);
 };