move MultiReader to lib

Author: yuk1ty

chapter3/src/3_7/main.rs

@@ -5,33 +5,7 @@ use std::{
     usize,
 };
 
-struct MultiReader<R> {
-    readers: Vec<R>,
-    pos: usize,
-}
-
-impl<R: Read> MultiReader<R> {
-    fn new(readers: Vec<R>) -> Self {
-        Self { readers, pos: 0 }
-    }
-}
-
-impl<R: Read> Read for MultiReader<R> {
-    fn read(&mut self, buf: &mut [u8]) -> std::io::Result<usize> {
-        loop {
-            match self.readers.get_mut(self.pos) {
-                Some(r) => {
-                    let n = r.read(buf)?;
-                    if n > 0 {
-                        return Ok(n);
-                    }
-                }
-                None => return Ok(0),
-            }
-            self.pos = self.pos + 1;
-        }
-    }
-}
+use lib::io::MultiReader;
 
 struct TeeReader<R, W>
 where

lib/src/io.rs

@@ -1,3 +1,5 @@
+mod multi_reader;
 mod multi_writer;
 
+pub use multi_reader::MultiReader;
 pub use multi_writer::MultiWriter;

lib/src/io/multi_reader.rs

@@ -0,0 +1,29 @@
+use std::io::Read;
+
+pub struct MultiReader<R> {
+    readers: Vec<R>,
+    pos: usize,
+}
+
+impl<R: Read> MultiReader<R> {
+    pub fn new(readers: Vec<R>) -> Self {
+        Self { readers, pos: 0 }
+    }
+}
+
+impl<R: Read> Read for MultiReader<R> {
+    fn read(&mut self, buf: &mut [u8]) -> std::io::Result<usize> {
+        loop {
+            match self.readers.get_mut(self.pos) {
+                Some(r) => {
+                    let n = r.read(buf)?;
+                    if n > 0 {
+                        return Ok(n);
+                    }
+                }
+                None => return Ok(0),
+            }
+            self.pos = self.pos + 1;
+        }
+    }
+}