TypeScript training - module 1 sample

module1.final.ts

const itemsList = [
    "eggs",
    "milk",
    "donuts",
    "butter",
    "coca-cola",
];

function itemize(items: string[]): string[] {
    return items
        .map((item, index) => `${index + 1}. ${item.substring(0, 1).toUpperCase()}${item.substring(1)}`);
}

const itemsToBuy = itemize(itemsList);

itemsToBuy.forEach((item) => console.log(item)); // tslint:disable-line no-console

// forces tsc to consider this file as a "module", so it doesn't conflict with other global declarations
export { };

module1.js

var itemsList = [
    "eggs",
    "milk",
    "donuts",
    "butter",
    "coca-cola"
];

/**
 * Converts items to Title-case and prefixed with item number
 * @param {string[]} items
 * @returns {string[]}
 */
function itemize(items) {
    // TODO: Converts items to Title-case and prefixed with item number

    return items;
}

var itemsToBuy = itemize(itemsList);

// EXPECTED:
// 1. Eggs
// 2. Milk
// 3. Donuts
// ...
itemsToBuy.forEach(item => console.log(item));

tslint.json

{
    "defaultSeverity": "error",
    "extends": [
        "tslint:recommended"
    ],
    "jsRules": {},
    "rules": {
        "quotemark": [true, "single"],
        "semicolon": [true, "always"],
        "prefer-const": true,
        "trailing-comma": [true, { "multiline": "always", "singleline": "never" }],
        "no-consecutive-blank-lines": true,
        "eofline": true,
        "indent": [true, "spaces", 4]
    },
    "rulesDirectory": []
}