refactor; add order() fn; add examples

examples/regex.rs

@@ -0,0 +1,39 @@
+use jsonfilter::{try_matches, FilterError};
+use serde_json::{json, Value};
+
+fn main() {
+    // You can filter text with regex
+    let filter = json!({"description": {"$regex": "(Rust|Python)"}});
+
+    let obj1 = json!({"name": "John Doe", "description": "Enthusiastic about programming in Rust"});
+    let obj2 = json!({"name": "Alice Smith", "description": "Experienced in web development"});
+    let obj3 = json!({"name": "Bob Brown", "description": "Loves to code in Python"});
+
+    println!("Filter:");
+    println!("{}", filter);
+    println!("Objects:");
+    println!("Object 1: {}", obj1);
+    println!("Object 2: {}", obj2);
+    println!("Object 3: {}", obj3);
+
+    match_objects(&filter, &obj1);
+    match_objects(&filter, &obj2);
+    match_objects(&filter, &obj3);
+}
+
+fn match_objects(filter: &Value, obj: &Value) {
+    match try_matches(filter, obj) {
+        Ok(result) => {
+            if result {
+                println!("Filter matches the object");
+            } else {
+                println!("Filter does not match the object");
+            }
+        }
+        Err(err) => match err {
+            FilterError::InvalidFilter => println!("Invalid filter"),
+            FilterError::UnknownOperator => println!("Unknown operator in filter"),
+            FilterError::KeyNotFound => println!("Key not found in object"),
+        },
+    }
+}