Add example doc for exit code usage

1 files changed, 57 insertions, 0 deletions

diff --git a/mingling/src/example_docs.rs b/mingling/src/example_docs.rs
index 0a6c1b9..09e84a8 100644
--- a/mingling/src/example_docs.rs
+++ b/mingling/src/example_docs.rs
@@ -343,6 +343,63 @@ pub mod example_completion {}
 /// gen_program!();
 /// ```
 pub mod example_dispatch_tree {}
+/// `Mingling` Example - Exit Code
+///
+///  This example demonstrates how to modify the program's exit code using `ExitCodeSetup`.
+///  By default, the program exits with code 0. This example shows:
+///  1. Using `dispatcher!` to define an error command,
+///  2. Using `chain!` to handle errors and set a custom exit code via `ProgramExitCode`,
+///  3. Using `renderer!` to print an error message.
+///
+///  # How to Run
+///  ```bash
+///  cargo run --manifest-path ./examples/example-exit-code/Cargo.toml -- error
+///  ```
+///
+/// Cargo.toml
+/// ```ignore
+/// [package]
+/// name = "example-exit-code"
+/// version = "0.1.0"
+/// edition = "2024"
+///
+/// [dependencies]
+/// mingling = { path = "../../mingling" }
+/// ```
+///
+/// main.rs
+/// ```ignore
+/// use mingling::{
+///     macros::{chain, dispatcher, gen_program, pack, r_println, renderer},
+///     res::ExitCode,
+///     setup::ExitCodeSetup,
+///     this,
+/// };
+///
+/// fn main() {
+///     let mut program = ThisProgram::new();
+///     program.with_dispatcher(ErrorCommand);
+///     program.with_setup(ExitCodeSetup::<ThisProgram>::default());
+///     program.exec();
+/// }
+///
+/// dispatcher!("error", ErrorCommand => ErrorEntry);
+/// pack!(ResultError = ());
+///
+/// #[chain]
+/// fn handle_error_entry(_prev: ErrorEntry) -> NextProcess {
+///     this::<ThisProgram>().modify_res(|r: &mut ExitCode| r.exit_code = 1);
+///     return ResultError::default();
+/// }
+///
+/// #[renderer]
+/// fn render_error(_prev: ResultError) {
+///     r_println!("Error!");
+/// }
+///
+/// gen_program!();
+/// ```
+pub mod example_exit_code {}
 /// `Mingling` Example - General Renderer
 ///
 ///  ## Step1 - Enable Feature