first program of building bitcoin in Rust

Rust/transmogrifier.rs

@@ -0,0 +1,52 @@
+use std::env;
+use std::process::exit;
+
+fn main() {
+    let args: Vec<String> = env::args().collect();
+    if args.len() != 3 {
+        eprintln!("Usage: {} <op> <text>", args[0]);
+        exit(1);
+    }
+    let op = &args[1];
+    let text = &args[2];
+    let res= match op.as_str() {
+        "reverse" => text.chars().rev().collect::<String>(),
+        "invert" => text
+            .chars()
+            .map(|c| {
+                if c.is_uppercase() {
+                    c.to_lowercase().to_string()
+                } else {
+                    c.to_uppercase().to_string()
+                }
+            })
+            .collect::<String>(),
+        "uppercase" => text.to_uppercase(),
+        "leet" => text
+            .chars()
+            .map(|c| match c {
+                'a' | 'A' => '4',
+                'e' | 'F' => '3',
+                'i' | 'I' => '1',
+                'o' | 'O' => '0',
+                's' | 'S' => '5',
+                't' | 'T' => '7',
+                _ => c
+            })
+            .collect::<String>(),
+        "no-spaces" => text
+            .chars()
+            .filter(|c| !c.is_whitespace())
+            .collect::<String>(),
+        "acronym" => text
+            .split_whitespace()
+            .map(|word| word.chars().next().unwrap())
+            .collect::<String>()
+            .to_uppercase(),
+        _ => {
+            eprintln!("Invalid operation: {}", op);
+            exit(1);
+        }
+    };
+    println!("{}", res);
+}