updated read files chapter

Author: donaldpipowitch

read-files/README.md

@@ -6,9 +6,10 @@
   "typings": "dist/index.d.ts",
   "scripts": {
     "start": "npm run build && node dist",
-    "build": "tsc"
+    "build": "tsc --build src"
   },
   "devDependencies": {
-    "typescript": "^1.8.10"
+    "@types/node": "^10.12.18",
+    "typescript": "^3.2.2"
   }
 }

read-files/node/dist/index.d.ts

@@ -1,36 +1,36 @@
-import { openSync, readSync, fstatSync } from 'fs';
+import { openSync, readSync, fstatSync, Stats } from 'fs';
 
-let file;
+let fileDescriptor: number;
 try {
-  file = openSync('hello.txt', 'r');
+  fileDescriptor = openSync('hello.txt', 'r');
 } catch (err) {
   console.log(`Couldn't open: ${err.message}`);
   process.exit(1);
 }
 
-let stat;
+let stat: Stats;
 try {
-  stat = fstatSync(file);
+  stat = fstatSync(fileDescriptor);
 } catch (err) {
   console.log(`Couldn't get stat: ${err.message}`);
   process.exit(1);
 }
 
-const buffer = new Buffer(stat.size);
+const buffer = Buffer.alloc(stat.size);
 
 try {
-  readSync(file, buffer, 0, stat.size, null);
+  readSync(fileDescriptor, buffer, 0, stat.size, null);
 } catch (err) {
   console.log(`Couldn't read: ${err.message}`);
   process.exit(1);
 }
 
-let data;
+let data: string;
 try {
   data = buffer.toString();
 } catch (err) {
   console.log(`Couldn't convert buffer to string: ${err.message}`);
   process.exit(1);
 }
 
-console.log(`Content is: ${data}`);
+console.log(`Content is: ${data}`);

read-files/node/dist/index.js

@@ -0,0 +1,9 @@
+{
+  "compilerOptions": {
+    "module": "commonjs",
+    "outDir": "../dist",
+    "declaration": true,
+    "sourceMap": true,
+    "declarationMap": true
+  }
+}