added ts util type and decorators

Author: santoshyadavdev

typescript-demo/datatypes.ts

@@ -1,3 +1,5 @@
+import { Employees } from "./interfaces";
+
 let fname: string;
 
 fname = "test";
@@ -116,8 +118,45 @@ function swap(num1: number, num2: number): [number, number] {
 
 type names = string | string[];
 
-let newName : names  = ['a','b']
+let newName: names = ["a", "b"];
+
+type taskStatus = "In Progress" | "Open" | "Closed";
+
+let newTask: taskStatus = "Open";
+
+let adam: Readonly<Employees> = {
+  id: 1,
+  email: "[email protected]",
+  dob: new Date("11-Mar-1986"),
+  department: "IT",
+  name: "test1",
+  salary: 10000,
+  data: "",
+};
+
+let { email: empemail, dob: empdbo } = adam;
+
+console.log(empemail);
+console.log(empdbo);
+
+// adam.salary = 20000;
+
+adam = { ...adam, salary: 20000 };
+
+// let empemail  = adam.email;
+// let dob = adam.dob;
+
+let ramesh: Partial<Employees> = {
+  id: 1,
+  email: "[email protected]",
+  dob: new Date("11-Mar-1986"),
+  department: "IT",
+  name: "test1",
+  // salary: 10000,
+  data: "",
+};
+
+type newEmployee = Pick<Employees, "email" | "dob">;
 
-type taskStatus = 'In Progress' | 'Open' | 'Closed';
+type newDepartment = Omit<Employees, 'salary' | 'dob'>;
 
-let newTask : taskStatus = 'Open';

typescript-demo/decorator.ts

@@ -0,0 +1,23 @@
+class Greeter {
+  greeting: string;
+  constructor(message: string) {
+    this.greeting = message;
+  }
+
+  @enumerable(false)
+  greet() {
+    return "Hello, " + this.greeting;
+  }
+}
+
+function enumerable(value: boolean) {
+  return function (
+    target: any,
+    propertyKey: string,
+    descriptor: PropertyDescriptor
+  ) {
+    console.log(target);
+    console.log(propertyKey);
+    descriptor.enumerable = value;
+  };
+}

typescript-demo/interfaces.ts

@@ -5,43 +5,43 @@ export interface Address<T> {
   city?: string;
   pin?: number;
   country?: string;
-  data : T;
+  data: T;
 }
 
-let address: Address<number> = {
+let address: Required<Address<number>> = {
   id: 1,
   addr1: "Pune",
+  addr2: "test",
   city: "Pune",
   country: "India",
   pin: 400000,
-  data : 10
+  data: 10,
 };
 
-interface Employees extends Address<string> {
+export interface Employees extends Address<string> {
   id: number;
   name: string;
   department: string;
   salary: number;
   email: string;
   dob: Date;
+  addressId: Pick<Address<string>, "id" | "addr1">;
 }
 
-
 interface Department {
-    id: number;
-    name: string;
+  id: number;
+  name: string;
 }
 
-
-let empList: Employees[] = [
+let empList: Readonly<Employees[]> = [
   {
     id: 1,
     email: "[email protected]",
     dob: new Date("11-Mar-1986"),
     department: "IT",
     name: "test1",
     salary: 10000,
-    data: '',
+    data: "",
   },
   {
     id: 2,
@@ -50,7 +50,7 @@ let empList: Employees[] = [
     department: "IT",
     name: "test2",
     salary: 15000,
-    data : '',
+    data: "",
   },
   {
     id: 3,
@@ -59,10 +59,21 @@ let empList: Employees[] = [
     department: "IT",
     name: "test3",
     salary: 20000,
-    data : ''
+    data: "",
   },
 ];
 
+let newEmp = {
+  id: 4,
+  email: "[email protected]",
+  dob: new Date("11-Mar-1990"),
+  department: "IT",
+  name: "test3",
+  salary: 20000,
+  data: "",
+};
+empList = [...empList, newEmp];
+
 let findEmp = empList.filter((emp) => emp.salary > 10000);
 
 console.table(findEmp);
@@ -75,7 +86,7 @@ export interface AddressUtil {
   add(num1: number, num2: number): number;
 }
 
-let testUnion : Employees[] | Department;
+let testUnion: Employees[] | Department;
 
 testUnion = empList;
 

typescript-demo/tsconfig.json

@@ -12,7 +12,7 @@
     // "jsx": "preserve",                     /* Specify JSX code generation: 'preserve', 'react-native', or 'react'. */
     // "declaration": true,                   /* Generates corresponding '.d.ts' file. */
     // "declarationMap": true,                /* Generates a sourcemap for each corresponding '.d.ts' file. */
-    "sourceMap": true,                     /* Generates corresponding '.map' file. */
+    "sourceMap": true /* Generates corresponding '.map' file. */,
     // "outFile": "./",                       /* Concatenate and emit output to single file. */
     "outDir": "./dist" /* Redirect output structure to the directory. */,
     // "rootDir": "./",                       /* Specify the root directory of input files. Use to control the output directory structure with --outDir. */
@@ -60,8 +60,8 @@
     // "inlineSources": true,                 /* Emit the source alongside the sourcemaps within a single file; requires '--inlineSourceMap' or '--sourceMap' to be set. */
 
     /* Experimental Options */
-    // "experimentalDecorators": true,        /* Enables experimental support for ES7 decorators. */
-    // "emitDecoratorMetadata": true,         /* Enables experimental support for emitting type metadata for decorators. */
+    "experimentalDecorators": true /* Enables experimental support for ES7 decorators. */,
+    "emitDecoratorMetadata": true /* Enables experimental support for emitting type metadata for decorators. */,
 
     /* Advanced Options */
     "skipLibCheck": true /* Skip type checking of declaration files. */,