Object Functions

/**
 * Gets the value at path of object
 * @param {Object} object - The object to query
 * @param {Array|string} path - The path of the property to get
 * @param {*} defaultValue - The value returned for undefined resolved values
 * @returns {*} Returns the resolved value
 */
function get(object, path, defaultValue);

/**
 * Checks if path is a direct property of object
 * @param {Object} object - The object to query
 * @param {Array|string} path - The path to check
 * @returns {boolean} Returns true if path exists, else false
 */
function has(object, path);

/**
 * Checks if path is a direct or inherited property of object
 * @param {Object} object - The object to query
 * @param {Array|string} path - The path to check
 * @returns {boolean} Returns true if path exists, else false
 */
function hasIn(object, path);

/**
 * Gets the value at path of object. If the resolved value is a function it's invoked
 * @param {Object} object - The object to query
 * @param {Array|string} path - The path of the property to get
 * @param {...*} args - The arguments to invoke the function with
 * @returns {*} Returns the resolved value
 */
function result(object, path, ...args);

/**
 * Sets the value at path of object
 * @param {Object} object - The object to modify
 * @param {Array|string} path - The path of the property to set
 * @param {*} value - The value to set
 * @returns {Object} Returns object
 */
function set(object, path, value);

/**
 * Like set but accepts customizer which is invoked to produce the objects of path
 * @param {Object} object - The object to modify
 * @param {Array|string} path - The path of the property to set
 * @param {*} value - The value to set
 * @param {Function} customizer - The function to customize assigned values
 * @returns {Object} Returns object
 */
function setWith(object, path, value, customizer);

/**
 * Removes the property at path of object
 * @param {Object} object - The object to modify
 * @param {Array|string} path - The path of the property to unset
 * @returns {boolean} Returns true if the property is deleted, else false
 */
function unset(object, path);

/**
 * Sets the value at path of object to the result of updater
 * @param {Object} object - The object to modify
 * @param {Array|string} path - The path of the property to update
 * @param {Function} updater - The function to produce the updated value
 * @returns {Object} Returns object
 */
function update(object, path, updater);

/**
 * Like update but accepts customizer which is invoked to produce the objects of path
 * @param {Object} object - The object to modify
 * @param {Array|string} path - The path of the property to update
 * @param {Function} updater - The function to produce the updated value
 * @param {Function} customizer - The function to customize assigned values
 * @returns {Object} Returns object
 */
function updateWith(object, path, updater, customizer);

/**
 * Creates an array of the own enumerable property names of object
 * @param {Object} object - The object to query
 * @returns {Array} Returns the array of property names
 */
function keys(object);

/**
 * Creates an array of the own and inherited enumerable property names of object
 * @param {Object} object - The object to query
 * @returns {Array} Returns the array of property names
 */
function keysIn(object);

/**
 * Creates an array of the own enumerable string keyed property values of object
 * @param {Object} object - The object to query
 * @returns {Array} Returns the array of property values
 */
function values(object);

/**
 * Creates an array of the own and inherited enumerable string keyed property values of object
 * @param {Object} object - The object to query
 * @returns {Array} Returns the array of property values
 */
function valuesIn(object);

/**
 * Creates an array of own enumerable string keyed-value pairs for object
 * @param {Object} object - The object to query
 * @returns {Array} Returns the key-value pairs
 */
function toPairs(object);

/**
 * Creates an array of own and inherited enumerable string keyed-value pairs for object
 * @param {Object} object - The object to query
 * @returns {Array} Returns the key-value pairs
 */
function toPairsIn(object);

/**
 * Alias for toPairs
 * @param {Object} object - The object to query
 * @returns {Array} Returns the key-value pairs
 */
function entries(object);

/**
 * Alias for toPairsIn
 * @param {Object} object - The object to query
 * @returns {Array} Returns the key-value pairs
 */
function entriesIn(object);

/**
 * Assigns own enumerable string keyed properties of source objects to the destination object
 * @param {Object} object - The destination object
 * @param {...Object} sources - The source objects
 * @returns {Object} Returns object
 */
function assign(object, ...sources);

/**
 * Like assign but iterates over own and inherited source properties
 * @param {Object} object - The destination object
 * @param {...Object} sources - The source objects
 * @returns {Object} Returns object
 */
function assignIn(object, ...sources);

/**
 * Like assign but accepts customizer which is invoked to produce the assigned values
 * @param {Object} object - The destination object
 * @param {...Object} sources - The source objects
 * @param {Function} customizer - The function to customize assigned values
 * @returns {Object} Returns object
 */
function assignWith(object, ...sources, customizer);

/**
 * Like assignIn but accepts customizer which is invoked to produce the assigned values
 * @param {Object} object - The destination object
 * @param {...Object} sources - The source objects
 * @param {Function} customizer - The function to customize assigned values
 * @returns {Object} Returns object
 */
function assignInWith(object, ...sources, customizer);

/**
 * Alias for assignIn
 * @param {Object} object - The destination object
 * @param {...Object} sources - The source objects
 * @returns {Object} Returns object
 */
function extend(object, ...sources);

/**
 * Alias for assignInWith
 * @param {Object} object - The destination object
 * @param {...Object} sources - The source objects
 * @param {Function} customizer - The function to customize assigned values
 * @returns {Object} Returns object
 */
function extendWith(object, ...sources, customizer);

/**
 * Recursively merges own and inherited enumerable string keyed properties of source objects
 * @param {Object} object - The destination object
 * @param {...Object} sources - The source objects
 * @returns {Object} Returns object
 */
function merge(object, ...sources);

/**
 * Like merge but accepts customizer which is invoked to produce the merged values
 * @param {Object} object - The destination object
 * @param {...Object} sources - The source objects
 * @param {Function} customizer - The function to customize assigned values
 * @returns {Object} Returns object
 */
function mergeWith(object, ...sources, customizer);

/**
 * Assigns own and inherited enumerable string keyed properties of source objects to the destination object for all destination properties that resolve to undefined
 * @param {Object} object - The destination object
 * @param {...Object} sources - The source objects
 * @returns {Object} Returns object
 */
function defaults(object, ...sources);

/**
 * Like defaults but recursively assigns default properties
 * @param {Object} object - The destination object
 * @param {...Object} sources - The source objects
 * @returns {Object} Returns object
 */
function defaultsDeep(object, ...sources);

/**
 * Creates an object composed of the picked object properties
 * @param {Object} object - The source object
 * @param {...(string|string[])} paths - The property paths to pick
 * @returns {Object} Returns the new object
 */
function pick(object, ...paths);

/**
 * Creates an object composed of the object properties predicate returns truthy for
 * @param {Object} object - The source object
 * @param {Function} predicate - The function invoked per property
 * @returns {Object} Returns the new object
 */
function pickBy(object, predicate);

/**
 * Creates an object composed of the own and inherited enumerable property paths of object that are not omitted
 * @param {Object} object - The source object
 * @param {...(string|string[])} paths - The property paths to omit
 * @returns {Object} Returns the new object
 */
function omit(object, ...paths);

/**
 * The opposite of pickBy; creates an object composed of the own and inherited enumerable string keyed properties of object that predicate doesn't return truthy for
 * @param {Object} object - The source object
 * @param {Function} predicate - The function invoked per property
 * @returns {Object} Returns the new object
 */
function omitBy(object, predicate);

/**
 * Creates an array of values corresponding to paths of object
 * @param {Object} object - The object to query
 * @param {...(string|string[])} paths - The property paths to get
 * @returns {Array} Returns the array of property values
 */
function at(object, ...paths);

/**
 * Iterates over own enumerable string keyed properties of an object and invokes iteratee for each property
 * @param {Object} object - The object to iterate over
 * @param {Function} iteratee - The function invoked per iteration
 * @returns {Object} Returns object
 */
function forOwn(object, iteratee);

/**
 * Like forOwn but iterates over properties in the opposite order
 * @param {Object} object - The object to iterate over
 * @param {Function} iteratee - The function invoked per iteration
 * @returns {Object} Returns object
 */
function forOwnRight(object, iteratee);

/**
 * Iterates over own and inherited enumerable string keyed properties of an object and invokes iteratee for each property
 * @param {Object} object - The object to iterate over
 * @param {Function} iteratee - The function invoked per iteration
 * @returns {Object} Returns object
 */
function forIn(object, iteratee);

/**
 * Like forIn but iterates over properties in the opposite order
 * @param {Object} object - The object to iterate over
 * @param {Function} iteratee - The function invoked per iteration
 * @returns {Object} Returns object
 */
function forInRight(object, iteratee);

/**
 * Returns the key of the first element predicate returns truthy for
 * @param {Object} object - The object to inspect
 * @param {Function} predicate - The function invoked per iteration
 * @returns {string|undefined} Returns the key of the matched element, else undefined
 */
function findKey(object, predicate);

/**
 * Like findKey but iterates over the object's properties in the opposite order
 * @param {Object} object - The object to inspect
 * @param {Function} predicate - The function invoked per iteration
 * @returns {string|undefined} Returns the key of the matched element, else undefined
 */
function findLastKey(object, predicate);

/**
 * Creates an object with the same values as object and keys generated by running each own enumerable string keyed property of object thru iteratee
 * @param {Object} object - The object to iterate over
 * @param {Function} iteratee - The function invoked per iteration
 * @returns {Object} Returns the new mapped object
 */
function mapKeys(object, iteratee);

/**
 * Creates an object with the same keys as object and values generated by running each own enumerable string keyed property of object thru iteratee
 * @param {Object} object - The object to iterate over
 * @param {Function} iteratee - The function invoked per iteration
 * @returns {Object} Returns the new mapped object
 */
function mapValues(object, iteratee);

/**
 * An alternative to _.reduce; this method transforms object to a new accumulator object
 * @param {Array|Object} object - The object to iterate over
 * @param {Function} iteratee - The function invoked per iteration
 * @param {*} accumulator - The custom accumulator value
 * @returns {*} Returns the accumulated value
 */
function transform(object, iteratee, accumulator);

/**
 * Creates an object composed of the inverted keys and values of object
 * @param {Object} object - The object to invert
 * @returns {Object} Returns the new inverted object
 */
function invert(object);

/**
 * Like invert but the inverted object is generated from the results of running each element of object thru iteratee
 * @param {Object} object - The object to invert
 * @param {Function} iteratee - The function invoked per iteration
 * @returns {Object} Returns the new inverted object
 */
function invertBy(object, iteratee);

/**
 * Creates an array of function property names from own enumerable properties of object
 * @param {Object} object - The object to inspect
 * @returns {Array} Returns the function names
 */
function functions(object);

/**
 * Creates an array of function property names from own and inherited enumerable properties of object
 * @param {Object} object - The object to inspect
 * @returns {Array} Returns the function names
 */
function functionsIn(object);

/**
 * Invokes the method at path of object
 * @param {Object} object - The object to query
 * @param {Array|string} path - The path of the method to invoke
 * @param {...*} args - The arguments to invoke the method with
 * @returns {*} Returns the result of the invoked method
 */
function invoke(object, path, ...args);

/**
 * Creates an object that inherits from the prototype object
 * @param {Object} prototype - The object to inherit from
 * @param {Object} properties - The properties to assign to the object
 * @returns {Object} Returns the new object
 */
function create(prototype, properties);

import { get, set, has, unset } from "lodash-es";

const user = {
  name: "Alice",
  profile: {
    age: 25,
    settings: {
      theme: "dark",
      notifications: true
    }
  }
};

// Get nested properties
const age = get(user, "profile.age"); // 25
const theme = get(user, "profile.settings.theme", "light"); // "dark"
const missing = get(user, "profile.bio", "No bio"); // "No bio"

// Check property existence
const hasAge = has(user, "profile.age"); // true
const hasBio = has(user, "profile.bio"); // false

// Set nested properties
set(user, "profile.bio", "Software engineer");
set(user, "profile.settings.language", "en");

// Remove properties
unset(user, "profile.settings.notifications");

import { assign, merge, defaults, pick, omit } from "lodash-es";

const target = { a: 1, b: 2 };
const source1 = { b: 3, c: 4 };
const source2 = { c: 5, d: 6 };

// Shallow assignment (modifies target)
assign(target, source1, source2); // { a: 1, b: 3, c: 5, d: 6 }

// Deep merging
const obj1 = { user: { name: "Alice", age: 25 } };
const obj2 = { user: { age: 26, city: "NYC" } };
const merged = merge({}, obj1, obj2); // { user: { name: "Alice", age: 26, city: "NYC" } }

// Set defaults
const config = { timeout: 1000 };
defaults(config, { timeout: 5000, retries: 3 }); // { timeout: 1000, retries: 3 }

// Pick and omit properties
const data = { name: "Alice", age: 25, password: "secret", email: "alice@example.com" };
const publicData = omit(data, ["password"]); // { name: "Alice", age: 25, email: "alice@example.com" }
const basicInfo = pick(data, ["name", "age"]); // { name: "Alice", age: 25 }

import { mapKeys, mapValues, transform, keys, values, toPairs } from "lodash-es";

const scores = { alice: 85, bob: 92, charlie: 78 };

// Transform keys
const upperKeys = mapKeys(scores, (value, key) => key.toUpperCase());
// { ALICE: 85, BOB: 92, CHARLIE: 78 }

// Transform values
const percentages = mapValues(scores, score => `${score}%`);
// { alice: "85%", bob: "92%", charlie: "78%" }

// Custom transformation
const result = transform(
  scores,
  (acc, score, name) => {
    if (score >= 80) {
      acc.push({ name, score, grade: "A" });
    }
  },
  []
);
// [{ name: "alice", score: 85, grade: "A" }, { name: "bob", score: 92, grade: "A" }]

// Extract keys, values, and pairs
const names = keys(scores); // ["alice", "bob", "charlie"]
const scoreValues = values(scores); // [85, 92, 78]
const pairs = toPairs(scores); // [["alice", 85], ["bob", 92], ["charlie", 78]]

import { findKey, invert, functions, invoke } from "lodash-es";

const users = {
  alice: { age: 25, active: true },
  bob: { age: 30, active: false },
  charlie: { age: 35, active: true }
};

// Find key by predicate
const firstActive = findKey(users, { active: true }); // "alice"
const over30 = findKey(users, user => user.age > 30); // "charlie"

// Invert object
const ageToName = invert(mapValues(users, "age")); // { "25": "alice", "30": "bob", "35": "charlie" }

// Work with function properties
const calculator = {
  add: (a, b) => a + b,
  multiply: (a, b) => a * b,
  name: "Calculator"
};

const methods = functions(calculator); // ["add", "multiply"]
const result = invoke(calculator, "add", 5, 3); // 8