Add not builtin command - ls

src/ls.rs

@@ -0,0 +1,36 @@
+use std::env;
+use std::fs;
+
+fn main(){
+    let args: Vec<String> = env::args().collect();
+    let pwd = env::current_dir().unwrap();
+    let mut show_hidden = false;
+    if args.len() == 1 {
+        list_dir(pwd.display().to_string(), show_hidden);
+    } else {
+        for arg in 1..args.len() {
+            match args[arg].as_str() {
+                "--help" => {
+                    println!("List files in directory");
+                },
+                "-a" | "--all" => {
+                    show_hidden = true;
+                },
+                arg => {
+                    list_dir(arg.to_string(), show_hidden);
+                },
+            }
+        }
+    }
+}         
+fn list_dir(arg: String, show_hidden: bool) {
+    let files = fs::read_dir(arg.clone()).unwrap();
+    for entry in files {
+        let path = entry.unwrap().path();
+        let file = path.strip_prefix(arg.clone());
+        if file.clone().unwrap().display().to_string().starts_with('.') && !show_hidden{
+            continue;
+        }
+        println!("{}", file.unwrap().display());
+    }
+}

src/mkdir.rs

@@ -9,16 +9,16 @@ fn main(){
             "--help" => {
                 println!("Usage: mkdir [OPTIONS] DIRECTORY");
                 return;
-            }
+            },
             "-v" | "--verbose" => {
                 verbose_flag = true;
-            }
+            },
             arg => {
                 fs::create_dir_all(arg.to_string());
                 if verbose_flag {
                     println!("mkdir: created directory '{}'", arg);
                 }
-            }
+            },
         }
     }
 }