move instructions to its seperate crate

src/instruction.rs

@@ -0,0 +1,17 @@
+#[derive(Debug)]
+pub enum InstructionType {
+    Increment,
+    Decrement,
+    Leftshift,
+    Rightshift,
+    PutChar,
+    GetChar,
+    JumpIfZero,
+    JumpIfNotZero,
+}
+
+#[derive(Debug)]
+pub struct Instruction {
+    pub itype: InstructionType,
+    pub argument: usize,
+}

src/lib.rs

@@ -1 +1,3 @@
 pub mod machine;
+pub mod parser;
+pub mod instruction;

src/machine.rs

@@ -1,22 +1,6 @@
 use std::io::{BufReader, BufWriter, Read, Write};
 
-#[derive(Debug)]
+use crate::instruction::{Instruction, InstructionType};
-pub enum InstructionType {
-    Increment,
-    Decrement,
-    Leftshift,
-    Rightshift,
-    PutChar,
-    GetChar,
-    JumpIfZero,
-    JumpIfNotZero,
-}
-
-#[derive(Debug)]
-pub struct Instruction {
-    pub itype: InstructionType,
-    pub argument: usize,
-}
 
 pub struct Machine<'a> {
     ip: usize,