docs(examples): Consoldate env examples

Author: epage

examples/env_list.rs

@@ -5,21 +5,26 @@ use std::sync::OnceLock;
 use config::Config;
 
 fn main() {
-    println!("{:?}", get::<String>("foo"));
+    println!("APP_STRING={:?}", get::<String>("string"));
+    println!("APP_INT={:?}", get::<i32>("int"));
+    println!("APP_STRLIST={:?}", get::<Vec<i32>>("strlist"));
 }
 
 /// Get a configuration value from the environment
-pub fn get<'a, T: serde::Deserialize<'a>>(path: &str) -> T {
-    // You shouldn't probably do it like that and actually handle that error that might happen
-    // here, but for the sake of simplicity, we do it like this here
-    config().get::<T>(path).unwrap()
+pub fn get<'a, T: serde::Deserialize<'a>>(path: &str) -> Option<T> {
+    config().get::<T>(path).ok()
 }
 
 fn config() -> &'static Config {
     static CONFIG: OnceLock<Config> = OnceLock::new();
     CONFIG.get_or_init(|| {
         Config::builder()
-            .add_source(config::Environment::with_prefix("APP"))
+            .add_source(
+                config::Environment::with_prefix("APP")
+                    .try_parsing(true)
+                    .separator("_")
+                    .list_separator(","),
+            )
             .build()
             .unwrap()
     })