Rework examples and add entry macro for testing

1 files changed, 97 insertions, 0 deletions

diff --git a/examples/example-error-handling/src/main.rs b/examples/example-error-handling/src/main.rs
new file mode 100644
index 0000000..d8db852
--- /dev/null
+++ b/examples/example-error-handling/src/main.rs
@@ -0,0 +1,97 @@
+//! Example Error Handling
+//!
+//! > This example demonstrates how to handle errors in Mingling, including custom error types and error rendering.
+//!
+//! Run:
+//! ```bash
+//! cargo run --manifest-path examples/example-error-handling/Cargo.toml --quiet -- hallo
+//! cargo run --manifest-path examples/example-error-handling/Cargo.toml --quiet -- hello
+//! cargo run --manifest-path examples/example-error-handling/Cargo.toml --quiet -- hello Alice
+//! cargo run --manifest-path examples/example-error-handling/Cargo.toml --quiet -- hello MyBestFriendAlice
+//! cargo run --manifest-path examples/example-error-handling/Cargo.toml --quiet -- hello Peter
+//! ```
+//!
+//! Output:
+//! ```plaintext
+//! Command not found: "hallo"
+//! No name provided
+//! Name not available
+//! Name too long: 17 > 10
+//! Hello, Peter
+//! ```
+
+use mingling::prelude::*;
+
+// In Mingling, instead of using ? to propagate errors upward,
+// errors are treated as branches that continue execution.
+
+dispatcher!("hello", CMDHello => EntryHello);
+
+// Define error types
+pack!(ErrorNoNameProvided = ());
+pack!(ErrorNameTooLong = u16);
+pack!(ErrorNameNotAvailable = ());
+
+// Define success type
+pack!(ResultName = String);
+
+// Pre-registered names
+static VEC_REGISTERED_NAMES: &[&str] = &["Alice", "Bob", "Charlie", "David", "Eve"];
+
+#[chain]
+fn handle_hello(args: EntryHello) -> Next {
+    let Some(name) = args.inner.first().cloned() else {
+        // If no name is provided, pass ErrorNoNameProvided
+        return ErrorNoNameProvided::default().to_render();
+    };
+
+    if name.len() > 10 {
+        // If the name is too long, pass ErrorNameTooLong
+        return ErrorNameTooLong::new(name.len() as u16).to_render();
+    }
+
+    if VEC_REGISTERED_NAMES.contains(&name.as_str()) {
+        // If the name already exists, pass ErrorNameNotAvailable
+        return ErrorNameNotAvailable::default().to_render();
+    }
+
+    // If the name is valid, pass ResultName
+    ResultName::new(name).to_render()
+}
+
+#[renderer]
+fn render_result_name(name: ResultName) {
+    r_println!("Hello, {}", *name);
+}
+
+#[renderer]
+fn render_error_no_name_provided(_: ErrorNoNameProvided) {
+    // Prompt when no name is provided
+    r_println!("No name provided");
+}
+
+#[renderer]
+fn render_error_name_not_available(_: ErrorNameNotAvailable) {
+    // Prompt when name is already taken
+    r_println!("Name not available");
+}
+
+#[renderer]
+fn render_error_name_too_long(len: ErrorNameTooLong) {
+    // Prompt when name is too long, showing actual length
+    r_println!("Name too long: {} > 10", *len);
+}
+
+#[renderer]
+fn render_dispatcher_not_found(err: DispatcherNotFound) {
+    // Prompt when command is not found, showing the input command
+    r_println!("Command not found: \"{}\"", err.inner.join(" "));
+}
+
+gen_program!();
+
+fn main() {
+    let mut program = ThisProgram::new();
+    program.with_dispatcher(CMDHello);
+    program.exec_and_exit();
+}