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libs/CLI11/book/chapters/an-advanced-example.md

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+# Making a git clone
+
+Let's try our hand at a little `git` clone, called `geet`. It will just print
+it's intent, rather than running actual code, since it's just a demonstration.
+Let's start by adding an app and requiring 1 subcommand to run:
+
+[include:"Intro"](../code/geet.cpp)
+
+Now, let's define the first subcommand, `add`, along with a few options:
+
+[include:"Add"](../code/geet.cpp)
+
+Now, let's add `commit`:
+
+[include:"Commit"](../code/geet.cpp)
+
+All that's need now is the parse call. We'll print a little message after the
+code runs, and then return:
+
+[include:"Parse"](../code/geet.cpp)
+
+[Source code](https://github.com/CLIUtils/CLI11/tree/main/book/code/geet.cpp)
+
+If you compile and run:
+
+```term
+gitbook:examples $ c++ -std=c++11 geet.cpp -o geet
+```
+
+You'll see it behaves pretty much like `git`.
+
+## Multi-file App parse code
+
+This example could be made much nicer if it was split into files, one per
+subcommand. If you simply use shared pointers instead of raw values in the
+lambda capture, you can tie the lifetime to the lambda function lifetime. CLI11
+has a
+[multifile example](https://github.com/CLIUtils/CLI11/tree/main/examples/subcom_in_files)
+in its example folder.