├── .gitignore ├── src ├── app.spec.ts ├── app.ts └── server.ts └── tsconfig.json /.gitignore: -------------------------------------------------------------------------------- 1 | .DS_Store 2 | dist 3 | -------------------------------------------------------------------------------- /src/app.spec.ts: -------------------------------------------------------------------------------- https://raw.githubusercontent.com/codersgyan/typescript-crash-course/54b45eadff3f492a02ae88b10d5baee1abdba07f/src/app.spec.ts -------------------------------------------------------------------------------- /src/app.ts: -------------------------------------------------------------------------------- 1 | // let num1 = 1; 2 | 3 | // function calculate(num1: number, num2: number) { 4 | // return num1 + num2; 5 | // } 6 | 7 | // console.log(calculate(num1, 3)); 8 | 9 | // function getTotal(numbers: Array) { 10 | // return numbers.reduce((acc, item) => { 11 | // return acc + item; 12 | // }, 0); 13 | // } 14 | 15 | // console.log(getTotal([3, 2, 1])); 16 | 17 | // const user = { 18 | // firstName: 'John', 19 | // lastName: 'Doe', 20 | // role: 'professor', 21 | // }; 22 | // console.log(user); 23 | 24 | // number 25 | // string 26 | // arr[] 27 | // boolean 28 | 29 | // Type alias 30 | 31 | // type User = { 32 | // name: string; 33 | // age: number; 34 | // address?: string; 35 | // }; 36 | 37 | // function login(userData: User): User { 38 | // return userData; 39 | // } 40 | 41 | // const user = { 42 | // name: 'Rakesh K', 43 | // age: 30, 44 | // }; 45 | 46 | // console.log(login(user)); 47 | 48 | // type ID = number | string; 49 | 50 | // const userId: ID = '123'; 51 | // Interfaces 52 | // interface Transaction { 53 | // payerAccountNumber: number; 54 | // payeeAccountNumber: number; 55 | // } 56 | 57 | // interface BankAccount { 58 | // accountNumber: number; 59 | // accountHolder: string; 60 | // balance: number; 61 | // isActive: boolean; 62 | // transactions: Transaction[]; 63 | // } 64 | 65 | // const transaction1: Transaction = { 66 | // payerAccountNumber: 123, 67 | // payeeAccountNumber: 455, 68 | // }; 69 | 70 | // const transaction2: Transaction = { 71 | // payerAccountNumber: 123, 72 | // payeeAccountNumber: 456, 73 | // }; 74 | 75 | // const bankAccount: BankAccount = { 76 | // accountNumber: 123, 77 | // accountHolder: 'John Doe', 78 | // balance: 4000, 79 | // isActive: true, 80 | // transactions: [transaction1, transaction2], 81 | // }; 82 | 83 | // Extend 84 | // interface Book { 85 | // name: string; 86 | // price: number; 87 | // } 88 | 89 | // interface EBook extends Book { 90 | // // name: string; 91 | // // price: number; 92 | // fileSize: number; 93 | // format: string; 94 | // } 95 | 96 | // interface AudioBook extends EBook { 97 | // // name: string; 98 | // // price: number; 99 | // // fileSize: number; 100 | // // format: string; 101 | // duration: number; 102 | // } 103 | 104 | // const book: AudioBook = { 105 | // name: 'Atomic habits', 106 | // price: 1200, 107 | // fileSize: 300, 108 | // format: 'pdf', 109 | // duration: 4, 110 | // }; 111 | 112 | // Merge 113 | // interface Book { 114 | // name: string; 115 | // price: number; 116 | // } 117 | 118 | // interface Book { 119 | // size: number; 120 | // } 121 | 122 | // const book: Book = { 123 | // name: 'Atomic habits', 124 | // price: 1200, 125 | // size: 45, 126 | // }; 127 | 128 | // type Book = { 129 | // name: string; 130 | // price: number; 131 | // } 132 | 133 | // type Book = { 134 | // size: number; 135 | // } 136 | 137 | // type SanitizedString = string; 138 | // type EvenNumber = number; 139 | 140 | // interface SanitizedString extends string { 141 | 142 | // } 143 | // Unions 144 | // type ID = number | string; 145 | // // Narrowing 146 | // function printId(id: ID) { 147 | // if (typeof id === 'string') { 148 | // console.log(id.toUpperCase()); 149 | // } else { 150 | // console.log(id); 151 | // } 152 | // } 153 | 154 | // printId('1'); 155 | 156 | // function getFirstThree(x: string | number[]) { 157 | // return x.slice(0, 3); 158 | // } 159 | 160 | // console.log(getFirstThree([1, 2, 3, 4, 5])); 161 | 162 | // Generics 163 | 164 | // function logString(arg: string) { 165 | // console.log(arg); 166 | // return arg; 167 | // } 168 | 169 | // function logNumber(arg: number) { 170 | // console.log(arg); 171 | // return arg; 172 | // } 173 | 174 | // function logArray(arg: any[]) { 175 | // console.log(arg); 176 | // return arg; 177 | // } 178 | 179 | // function logAnything(arg: T): T { 180 | // console.log(arg); 181 | // return arg; 182 | // } 183 | 184 | // logAnything(['hello']); 185 | 186 | // interface HasAge { 187 | // age: number; 188 | // } 189 | 190 | // function getOldest(people: T[]): T { 191 | // return people.sort((a, b) => b.age - a.age)[0]; 192 | // } 193 | 194 | // const people: HasAge[] = [{ age: 30 }, { age: 40 }, { age: 10 }]; 195 | 196 | // interface Player { 197 | // name: string; 198 | // age: number; 199 | // } 200 | // const players: Player[] = [ 201 | // { name: 'John', age: 30 }, 202 | // { name: 'Jane', age: 35 }, 203 | // { name: 'Joe', age: 16 }, 204 | // ]; 205 | // // Assertion 206 | // // const person = getOldest(players) as Player; 207 | 208 | // const person = getOldest(people); 209 | // // Generics 210 | // person.age; 211 | 212 | interface IPost { 213 | title: string; 214 | id: number; 215 | description: string; 216 | } 217 | 218 | interface IUser { 219 | id: number; 220 | name: string; 221 | age: number; 222 | } 223 | 224 | // const fetchPostData = async (path: string): Promise => { 225 | // const response = await fetch(`http://example.com${path}`); 226 | // return response.json(); 227 | // }; 228 | 229 | // const fetchUsersData = async (path: string): Promise => { 230 | // const response = await fetch(`http://example.com${path}`); 231 | // return response.json(); 232 | // }; 233 | 234 | // const fetchData = async (path: string): Promise => { 235 | // const response = await fetch(`http://example.com${path}`); 236 | // return response.json(); 237 | // } 238 | 239 | // (async () => { 240 | // // const posts = await fetchPostData('/posts'); 241 | // const posts = await fetchData('/posts'); 242 | // posts[0]. 243 | // })(); 244 | 245 | // Structural typing or duck typing 246 | // interface ICreadential { 247 | // username: string; 248 | // password: string; 249 | // isAdmin?: boolean; 250 | // } 251 | 252 | // function login(credentials: ICreadential): boolean { 253 | // console.log(credentials); 254 | // return true; 255 | // } 256 | 257 | // const user = { 258 | // username: 'codersgyan', 259 | // password: 'secret', 260 | // isAdmin: true, 261 | // }; 262 | 263 | // login(user); 264 | // interface IAuth { 265 | // username: string; 266 | // password: string; 267 | // login(username: string, password: string): boolean; 268 | // } 269 | 270 | // const auth: IAuth = { 271 | // username: 'codersgyan', 272 | // password: 'secret', 273 | // login(username: string, password: string) { 274 | // return true; 275 | // } 276 | // } 277 | 278 | // inference 279 | // let num = 'Coders'; 280 | -------------------------------------------------------------------------------- /src/server.ts: -------------------------------------------------------------------------------- 1 | console.log('hello'); 2 | -------------------------------------------------------------------------------- /tsconfig.json: -------------------------------------------------------------------------------- 1 | { 2 | "compilerOptions": { 3 | /* Visit https://aka.ms/tsconfig to read more about this file */ 4 | 5 | /* Projects */ 6 | // "incremental": true, /* Save .tsbuildinfo files to allow for incremental compilation of projects. */ 7 | // "composite": true, /* Enable constraints that allow a TypeScript project to be used with project references. */ 8 | // "tsBuildInfoFile": "./.tsbuildinfo", /* Specify the path to .tsbuildinfo incremental compilation file. */ 9 | // "disableSourceOfProjectReferenceRedirect": true, /* Disable preferring source files instead of declaration files when referencing composite projects. */ 10 | // "disableSolutionSearching": true, /* Opt a project out of multi-project reference checking when editing. */ 11 | // "disableReferencedProjectLoad": true, /* Reduce the number of projects loaded automatically by TypeScript. */ 12 | 13 | /* Language and Environment */ 14 | "target": "es2016", /* Set the JavaScript language version for emitted JavaScript and include compatible library declarations. */ 15 | // "lib": [], /* Specify a set of bundled library declaration files that describe the target runtime environment. */ 16 | // "jsx": "preserve", /* Specify what JSX code is generated. */ 17 | // "experimentalDecorators": true, /* Enable experimental support for TC39 stage 2 draft decorators. */ 18 | // "emitDecoratorMetadata": true, /* Emit design-type metadata for decorated declarations in source files. */ 19 | // "jsxFactory": "", /* Specify the JSX factory function used when targeting React JSX emit, e.g. 'React.createElement' or 'h'. */ 20 | // "jsxFragmentFactory": "", /* Specify the JSX Fragment reference used for fragments when targeting React JSX emit e.g. 'React.Fragment' or 'Fragment'. */ 21 | // "jsxImportSource": "", /* Specify module specifier used to import the JSX factory functions when using 'jsx: react-jsx*'. */ 22 | // "reactNamespace": "", /* Specify the object invoked for 'createElement'. This only applies when targeting 'react' JSX emit. */ 23 | // "noLib": true, /* Disable including any library files, including the default lib.d.ts. */ 24 | // "useDefineForClassFields": true, /* Emit ECMAScript-standard-compliant class fields. */ 25 | // "moduleDetection": "auto", /* Control what method is used to detect module-format JS files. */ 26 | 27 | /* Modules */ 28 | "module": "commonjs", /* Specify what module code is generated. */ 29 | // "rootDir": "./", /* Specify the root folder within your source files. */ 30 | // "moduleResolution": "node", /* Specify how TypeScript looks up a file from a given module specifier. */ 31 | // "baseUrl": "./", /* Specify the base directory to resolve non-relative module names. */ 32 | // "paths": {}, /* Specify a set of entries that re-map imports to additional lookup locations. */ 33 | // "rootDirs": [], /* Allow multiple folders to be treated as one when resolving modules. */ 34 | // "typeRoots": [], /* Specify multiple folders that act like './node_modules/@types'. */ 35 | // "types": [], /* Specify type package names to be included without being referenced in a source file. */ 36 | // "allowUmdGlobalAccess": true, /* Allow accessing UMD globals from modules. */ 37 | // "moduleSuffixes": [], /* List of file name suffixes to search when resolving a module. */ 38 | // "resolveJsonModule": true, /* Enable importing .json files. */ 39 | // "noResolve": true, /* Disallow 'import's, 'require's or ''s from expanding the number of files TypeScript should add to a project. */ 40 | 41 | /* JavaScript Support */ 42 | // "allowJs": true, /* Allow JavaScript files to be a part of your program. Use the 'checkJS' option to get errors from these files. */ 43 | // "checkJs": true, /* Enable error reporting in type-checked JavaScript files. */ 44 | // "maxNodeModuleJsDepth": 1, /* Specify the maximum folder depth used for checking JavaScript files from 'node_modules'. Only applicable with 'allowJs'. */ 45 | 46 | /* Emit */ 47 | // "declaration": true, /* Generate .d.ts files from TypeScript and JavaScript files in your project. */ 48 | // "declarationMap": true, /* Create sourcemaps for d.ts files. */ 49 | // "emitDeclarationOnly": true, /* Only output d.ts files and not JavaScript files. */ 50 | // "sourceMap": true, /* Create source map files for emitted JavaScript files. */ 51 | // "outFile": "./", /* Specify a file that bundles all outputs into one JavaScript file. If 'declaration' is true, also designates a file that bundles all .d.ts output. */ 52 | "outDir": "./dist", /* Specify an output folder for all emitted files. */ 53 | // "removeComments": true, /* Disable emitting comments. */ 54 | // "noEmit": true, /* Disable emitting files from a compilation. */ 55 | // "importHelpers": true, /* Allow importing helper functions from tslib once per project, instead of including them per-file. */ 56 | // "importsNotUsedAsValues": "remove", /* Specify emit/checking behavior for imports that are only used for types. */ 57 | // "downlevelIteration": true, /* Emit more compliant, but verbose and less performant JavaScript for iteration. */ 58 | // "sourceRoot": "", /* Specify the root path for debuggers to find the reference source code. */ 59 | // "mapRoot": "", /* Specify the location where debugger should locate map files instead of generated locations. */ 60 | // "inlineSourceMap": true, /* Include sourcemap files inside the emitted JavaScript. */ 61 | // "inlineSources": true, /* Include source code in the sourcemaps inside the emitted JavaScript. */ 62 | // "emitBOM": true, /* Emit a UTF-8 Byte Order Mark (BOM) in the beginning of output files. */ 63 | // "newLine": "crlf", /* Set the newline character for emitting files. */ 64 | // "stripInternal": true, /* Disable emitting declarations that have '@internal' in their JSDoc comments. */ 65 | // "noEmitHelpers": true, /* Disable generating custom helper functions like '__extends' in compiled output. */ 66 | // "noEmitOnError": true, /* Disable emitting files if any type checking errors are reported. */ 67 | // "preserveConstEnums": true, /* Disable erasing 'const enum' declarations in generated code. */ 68 | // "declarationDir": "./", /* Specify the output directory for generated declaration files. */ 69 | // "preserveValueImports": true, /* Preserve unused imported values in the JavaScript output that would otherwise be removed. */ 70 | 71 | /* Interop Constraints */ 72 | // "isolatedModules": true, /* Ensure that each file can be safely transpiled without relying on other imports. */ 73 | // "allowSyntheticDefaultImports": true, /* Allow 'import x from y' when a module doesn't have a default export. */ 74 | "esModuleInterop": true, /* Emit additional JavaScript to ease support for importing CommonJS modules. This enables 'allowSyntheticDefaultImports' for type compatibility. */ 75 | // "preserveSymlinks": true, /* Disable resolving symlinks to their realpath. This correlates to the same flag in node. */ 76 | "forceConsistentCasingInFileNames": true, /* Ensure that casing is correct in imports. */ 77 | 78 | /* Type Checking */ 79 | "strict": true, /* Enable all strict type-checking options. */ 80 | // "noImplicitAny": true, /* Enable error reporting for expressions and declarations with an implied 'any' type. */ 81 | // "strictNullChecks": true, /* When type checking, take into account 'null' and 'undefined'. */ 82 | // "strictFunctionTypes": true, /* When assigning functions, check to ensure parameters and the return values are subtype-compatible. */ 83 | // "strictBindCallApply": true, /* Check that the arguments for 'bind', 'call', and 'apply' methods match the original function. */ 84 | // "strictPropertyInitialization": true, /* Check for class properties that are declared but not set in the constructor. */ 85 | // "noImplicitThis": true, /* Enable error reporting when 'this' is given the type 'any'. */ 86 | // "useUnknownInCatchVariables": true, /* Default catch clause variables as 'unknown' instead of 'any'. */ 87 | // "alwaysStrict": true, /* Ensure 'use strict' is always emitted. */ 88 | // "noUnusedLocals": true, /* Enable error reporting when local variables aren't read. */ 89 | // "noUnusedParameters": true, /* Raise an error when a function parameter isn't read. */ 90 | // "exactOptionalPropertyTypes": true, /* Interpret optional property types as written, rather than adding 'undefined'. */ 91 | // "noImplicitReturns": true, /* Enable error reporting for codepaths that do not explicitly return in a function. */ 92 | // "noFallthroughCasesInSwitch": true, /* Enable error reporting for fallthrough cases in switch statements. */ 93 | // "noUncheckedIndexedAccess": true, /* Add 'undefined' to a type when accessed using an index. */ 94 | // "noImplicitOverride": true, /* Ensure overriding members in derived classes are marked with an override modifier. */ 95 | // "noPropertyAccessFromIndexSignature": true, /* Enforces using indexed accessors for keys declared using an indexed type. */ 96 | // "allowUnusedLabels": true, /* Disable error reporting for unused labels. */ 97 | // "allowUnreachableCode": true, /* Disable error reporting for unreachable code. */ 98 | 99 | /* Completeness */ 100 | // "skipDefaultLibCheck": true, /* Skip type checking .d.ts files that are included with TypeScript. */ 101 | "skipLibCheck": true /* Skip type checking all .d.ts files. */ 102 | }, 103 | "include": ["src/**/*"], 104 | "exclude": ["node_modules", "**/*.spec.ts"] 105 | } 106 | --------------------------------------------------------------------------------