Examples for 3.3

Author: samerbuna

3.3/errors.js

@@ -0,0 +1,31 @@
+const fs = require('fs');
+const EventEmitter = require('events');
+
+class WithTime extends EventEmitter {
+  execute(asyncFunc, ...args) {
+    console.time('execute');
+    asyncFunc(...args, (err, data) => {
+      if (err) {
+        return this.emit('error', err);
+      }
+
+      this.emit('data', data);
+      console.timeEnd('execute');
+    });
+  }
+}
+
+const withTime = new WithTime();
+
+withTime.on('data', (data) => {
+  console.log(`Length: ${data.length}`);
+});
+
+process.once('uncaughtException', (err) => {
+  console.log(err);
+  // do some cleanup
+  process.exit(1); // exit anyway
+});
+
+withTime.execute(fs.readFile, '');
+withTime.execute(fs.readFile, __filename);

3.3/order.js

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+const fs = require('fs');
+const EventEmitter = require('events');
+
+class WithTime extends EventEmitter {
+  execute(asyncFunc, ...args) {
+    console.time('execute');
+    asyncFunc(...args, (err, data) => {
+      if (err) {
+        return this.emit('error', err);
+      }
+
+      this.emit('data', data);
+      console.timeEnd('execute');
+    });
+  }
+}
+
+const withTime = new WithTime();
+
+// प्रथम
+withTime.on('data', (data) => {
+  console.log(`Length: ${data.length}`);
+});
+
+// दूसरा
+withTime.prependListener('data', (data) => {
+  console.log(`Charaters: ${data.toString().length}`);
+});
+
+// withTime.removeListener ...
+
+withTime.execute(fs.readFile, __filename);