Lodash ForEach

var forEach = require('lodash.foreach');

import forEach from 'lodash.foreach';

var forEach = require('lodash.foreach');
// or import forEach from 'lodash.foreach';

// Array iteration
forEach([1, 2, 3], function(value, index, array) {
  console.log(value);
});
// => 1 2 3

// Object iteration  
forEach({ 'a': 1, 'b': 2 }, function(value, key, object) {
  console.log(key + ': ' + value);
});
// => a: 1 b: 2

// String iteration
forEach('abc', function(char, index, string) {
  console.log(char);
});
// => a b c

// With binding context
var context = { multiplier: 2 };
forEach([1, 2, 3], function(value) {
  console.log(value * this.multiplier);
}, context);
// => 2 4 6

// Early exit by returning false
forEach([1, 2, 3, 4, 5], function(value) {
  if (value === 3) return false;
  console.log(value);
});
// => 1 2

/**
 * Iterates over elements of collection invoking iteratee for each element.
 * The iteratee is bound to thisArg and invoked with three arguments:
 * (value, index|key, collection). Iteratee functions may exit iteration 
 * early by explicitly returning false.
 * 
 * @param {Array|Object|string} collection - The collection to iterate over
 * @param {Function} [iteratee] - The function invoked per iteration
 * @param {*} [thisArg] - The this binding of iteratee  
 * @returns {Array|Object|string} Returns collection
 */
function forEach(collection, iteratee, thisArg);

var forEach = require('lodash.foreach');

// Basic array iteration with return value
var result = forEach([1, 2], function(n) {
  console.log(n);
});
// => logs each value from left to right and returns the array
// result equals [1, 2]

// Object iteration with guaranteed behavior
forEach({ 'user1': { 'active': true }, 'user2': { 'active': false } }, 
  function(user, key) {
    if (user.active) {
      console.log(key + ' is active');
    }
  }
);

// String character iteration
forEach('hello', function(char, index) {
  console.log('char at ' + index + ': ' + char);
});

// Early termination example
var found = false;
forEach([1, 2, 3, 4, 5], function(value) {
  if (value === 3) {
    found = true;
    return false; // Exit early
  }
  console.log('Processing: ' + value);
});
// => Processing: 1, Processing: 2

// Performance optimization - no thisArg binding for arrays
forEach(largeArray, function(item, index) {
  // Fast array iteration path
  processItem(item);
});

// Binding context for complex operations
var processor = {
  prefix: '[LOG]',
  process: function(items) {
    forEach(items, function(item) {
      console.log(this.prefix + ' ' + item);
    }, this);
  }
};

// Array-like objects with length property are treated as arrays
var arrayLike = { 0: 'a', 1: 'b', 2: 'c', length: 3 };
forEach(arrayLike, function(value, index) {
  console.log(index + ': ' + value);
});
// => 0: a, 1: b, 2: c

// Edge case handling - non-function iteratee
var result = forEach([1, 2, 3]); // No iteratee provided
console.log(result); // => [1, 2, 3] (original array returned)

// Edge case handling - null/undefined collections
forEach(null, function() {}); // => null (handled safely)
forEach(undefined, function() {}); // => undefined (handled safely)

// Demonstrating that original reference is returned
var original = [1, 2, 3];
var returned = forEach(original, function(n) { console.log(n); });
console.log(original === returned); // => true (same reference)