output

Author: lencx

cli/grrs/src/main.rs

@@ -1,11 +1,10 @@
-// use std::env;
 use std::fs::{self, File};
 use std::io::{self, BufReader, prelude::*};
 use std::path::Path;
 use structopt::StructOpt;
 
 // Search for a pattern in a file and display the lines that contain it.
-#[derive(StructOpt)]
+#[derive(StructOpt, Debug)]
 struct Cli {
     /// The pattern to look for
     pattern: String,
@@ -15,16 +14,40 @@ struct Cli {
 }
 
 fn main() {
+    eprintln!("This is an error! :(");
     let args = Cli::from_args();
-    if let Ok(lines) = read_line(&args.path) {
-        for line in lines {
-            if let Ok(_line) = line {
-                if _line.contains(&args.pattern) {
-                    println!("{:?}", _line);
+    println!("======= args =======");
+    println!("{:#?}", args);
+    // Option 1.
+    let result = read_line(&args.path);
+    match result {
+        Ok(content) => {
+            // println!("file content: {:?}", content);
+            for (index, line) in content.enumerate() {
+                if let Ok(_line) = line {
+                    if _line.contains(&args.pattern) {
+                        println!("======= match line [{}] =======", index);
+                        println!("{}", _line);
+                    }
                 }
             }
-        }
+        },
+        Err(err) => println!("Oh noes: {}", err)
     }
+
+    // read_content(&args.path);
+
+    // // Option 2.
+    // if let Ok(lines) = read_line(&args.path) {
+    //     for (index, line) in lines.enumerate() {
+    //         if let Ok(_line) = line {
+    //             if _line.contains(&args.pattern) {
+    //                 println!("======= match line [{}] =======", index);
+    //                 println!("{}", _line);
+    //             }
+    //         }
+    //     }
+    // }
 }
 
 /// @see: https://doc.rust-lang.org/stable/rust-by-example/std_misc/file/read_lines.html
@@ -36,6 +59,7 @@ where P: AsRef<Path> {
 
 // fn main() {
 //     let args = Cli::from_args();
+//     // let mut content = fs::read_to_string(&args.path)?;
 //     let mut content = fs::read_to_string(&args.path).expect("could not read file");
 
 //     for line in content.lines() {
@@ -44,3 +68,14 @@ where P: AsRef<Path> {
 //         }
 //     }
 // }
+
+fn read_content<P>(filename: P) -> Result<(), Box<dyn std::error::Error>>
+where P: AsRef<Path> {
+    let result = fs::read_to_string(filename);
+    let content = match result {
+        Ok(content) => { content },
+        Err(err) => { return Err(err.into()); },
+    };
+    // println!("file content: {}", content);
+    Ok(())
+}

example/ch18/output_for_humans_and_machines/Cargo.toml

@@ -0,0 +1,12 @@
+[package]
+name = "output_for_humans_and_machines"
+version = "0.1.0"
+authors = ["lencx <[email protected]>"]
+edition = "2018"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+indicatif = "0.14.0"
+log = "0.4.0"
+env_logger = "0.7.1"

example/ch18/output_for_humans_and_machines/src/bin/output-log.rs

@@ -0,0 +1,9 @@
+#[macro_use]
+extern crate log;
+
+fn main() {
+    // RUST_LOG=info cargo run --bin output-log
+    env_logger::init();
+    info!("starting up");
+    warn!("oops, nothing implemented!");
+}

example/ch18/output_for_humans_and_machines/src/main.rs

@@ -0,0 +1,17 @@
+use std::io::{self, Write};
+
+fn main() {
+    // get the global stdout entity
+    let stdout = io::stdout();
+
+    // acquire a lock on it
+    let mut handle = stdout.lock();
+    writeln!(handle, "foo: {}", 42);
+
+    let pb = indicatif::ProgressBar::new(100);
+    for i in 0..100 {
+        pb.println(format!("[+] finished #{}", i));
+        pb.inc(1);
+    }
+    pb.finish_with_message("done");
+}