Git Submodule Update: Methods to Keep Dependencies in Sync

Git submodules are used to address the trouble of code reuse and avoid repeated pasting. The main repository only records the version and location of the sub-repositories, while the sub-repositories store the actual code. Their uses include team sharing of components, version control of third-party dependencies, and code isolation. Usage steps: To clone a repository with nested submodules, use `git clone --recursive`. To initialize and update submodules, use `git submodule update --init --recursive` (to recursively update nested submodules). To update submodules and pull the latest versions, execute `git submodule update --recursive`. After modifying a submodule, first commit within the submodule, then return to the main project, execute `git add <submodule directory>` and `git commit` to update the main project's reference. After pulling updates to the main project, synchronize the submodules. Common issues: If the directory is empty, initialize it. If the version is incorrect, perform a recursive update. If changes were made without syncing the main project, add and commit the reference. Submodules are like Lego parts—independent and reusable. The key points to remember are "clone with --recursive, update and sync with --recursive, and sync references after modifications."