| 4 | 4 | // |
| 5 | 5 | |
| 6 | 6 | export class List { |
| 7 | | constructor() { |
| 8 | | throw new Error('Remove this line and implement the function'); |
| 7 | /** |
| 8 | * Creates a new List instance. |
| 9 | * @param {Array} [values=[]] - Initial values for the list. |
| 10 | */ |
| 11 | constructor(values = []) { |
| 12 | this.values = values; |
| 9 | 13 | } |
| 10 | 14 | |
| 11 | 15 | /** |
| 12 | | * @param {List} other |
| 13 | | * @return {List} |
| 16 | * Appends another list to this list. |
| 17 | * @param {List} other - The list to append. |
| 18 | * @return {List} A new list containing elements from both lists. |
| 19 | * |
| 20 | * Handled Edge Cases: Empty lists, null/undefined other list |
| 14 | 21 | */ |
| 15 | 22 | append(other) { |
| 16 | | throw new Error('Remove this line and implement the function'); |
| 23 | // Edge Case: Handle when other is not a List instance |
| 24 | if (!(other instanceof List)) { |
| 25 | throw new Error('Argument must be a List'); |
| 26 | } |
| 27 | |
| 28 | // Edge Case: Handle empty lists |
| 29 | if (this.values.length === 0 && other.values.length === 0) { |
| 30 | return new List([]); |
| 31 | } |
| 32 | |
| 33 | return new List([...this.values, ...other.values]); |
| 17 | 34 | } |
| 18 | 35 | |
| 19 | 36 | /** |
| 20 | | * @param {List} others |
| 21 | | * @return {List} |
| 37 | * Concatenates multiple lists into one. |
| 38 | * @param {List} others - A list of lists to concatenate. |
| 39 | * @return {List} A new list with all elements from all lists. |
| 40 | * |
| 41 | * Handled Edge Cases: Empty lists, nested empty lists |
| 22 | 42 | */ |
| 23 | 43 | concat(others) { |
| 24 | | throw new Error('Remove this line and implement the function'); |
| 44 | // Edge Case: Handle when others is not a List instance |
| 45 | if (!(others instanceof List)) { |
| 46 | throw new Error('Argument must be a List'); |
| 47 | } |
| 48 | |
| 49 | let result = [...this.values]; |
| 50 | |
| 51 | // Edge Case: Handle empty others list |
| 52 | if (others.values.length === 0) { |
| 53 | return new List(result); |
| 54 | } |
| 55 | |
| 56 | for (const list of others.values) { |
| 57 | // Edge Case: Handle when an element in others is not a List |
| 58 | if (!(list instanceof List)) { |
| 59 | throw new Error('All elements in others must be Lists'); |
| 60 | } |
| 61 | result = [...result, ...list.values]; |
| 62 | } |
| 63 | |
| 64 | return new List(result); |
| 25 | 65 | } |
| 26 | 66 | |
| 27 | 67 | /** |
| 28 | | * @param {(any) => boolean} predicate |
| 29 | | * @return {List} |
| 68 | * Filters the list based on a predicate function. |
| 69 | * @param {(any) => boolean} predicate - Function to test each element. |
| 70 | * @return {List} A new list with elements that pass the predicate test. |
| 71 | * |
| 72 | * Handled Edge Cases: Empty list, predicate function throwing errors |
| 30 | 73 | */ |
| 31 | 74 | filter(predicate) { |
| 32 | | throw new Error('Remove this line and implement the function'); |
| 75 | // Edge Case: Handle when predicate is not a function |
| 76 | if (typeof predicate !== 'function') { |
| 77 | throw new Error('Predicate must be a function'); |
| 78 | } |
| 79 | |
| 80 | const result = []; |
| 81 | |
| 82 | // Edge Case: Handle empty list |
| 83 | if (this.values.length === 0) { |
| 84 | return new List([]); |
| 85 | } |
| 86 | |
| 87 | for (const value of this.values) { |
| 88 | try { |
| 89 | if (predicate(value)) { |
| 90 | result.push(value); |
| 91 | } |
| 92 | } catch (error) { |
| 93 | // Edge Case: Handle errors in predicate function |
| 94 | throw new Error(`Predicate function error: ${error.message}`); |
| 95 | } |
| 96 | } |
| 97 | |
| 98 | return new List(result); |
| 33 | 99 | } |
| 34 | 100 | |
| 35 | 101 | /** |
| 36 | | * @param {(any) => any} expression |
| 37 | | * @return {List} |
| 102 | * Maps each element using a provided function. |
| 103 | * @param {(any) => any} expression - Function to transform each element. |
| 104 | * @return {List} A new list with transformed elements. |
| 105 | * |
| 106 | * Handled Edge Cases: Empty list, expression function throwing errors |
| 38 | 107 | */ |
| 39 | 108 | map(expression) { |
| 40 | | throw new Error('Remove this line and implement the function'); |
| 109 | // Edge Case: Handle when expression is not a function |
| 110 | if (typeof expression !== 'function') { |
| 111 | throw new Error('Expression must be a function'); |
| 112 | } |
| 113 | |
| 114 | const result = []; |
| 115 | |
| 116 | // Edge Case: Handle empty list |
| 117 | if (this.values.length === 0) { |
| 118 | return new List([]); |
| 119 | } |
| 120 | |
| 121 | for (const value of this.values) { |
| 122 | try { |
| 123 | result.push(expression(value)); |
| 124 | } catch (error) { |
| 125 | // Edge Case: Handle errors in expression function |
| 126 | throw new Error(`Expression function error: ${error.message}`); |
| 127 | } |
| 128 | } |
| 129 | |
| 130 | return new List(result); |
| 41 | 131 | } |
| 42 | 132 | |
| 43 | 133 | /** |
| 44 | | * @return {number} |
| 134 | * Returns the length of the list. |
| 135 | * @return {number} The number of elements in the list. |
| 136 | * |
| 137 | * Handled Edge Cases: None (this operation is always safe) |
| 45 | 138 | */ |
| 46 | 139 | length() { |
| 47 | | throw new Error('Remove this line and implement the function'); |
| 140 | return this.values.length; |
| 48 | 141 | } |
| 49 | 142 | |
| 50 | 143 | /** |
| 51 | | * @param {(acc: any, el: any) => any} callback |
| 52 | | * @param {any} initial |
| 53 | | * @return {any} |
| 144 | * Folds the list from the left using a callback function. |
| 145 | * @param {(acc: any, el: any) => any} callback - Function to apply to each element. |
| 146 | * @param {any} initial - Initial accumulator value. |
| 147 | * @return {any} The final accumulator value. |
| 148 | * |
| 149 | * Handled Edge Cases: Empty list, callback function throwing errors |
| 54 | 150 | */ |
| 55 | 151 | foldl(callback, initial) { |
| 56 | | throw new Error('Remove this line and implement the function'); |
| 152 | // Edge Case: Handle when callback is not a function |
| 153 | if (typeof callback !== 'function') { |
| 154 | throw new Error('Callback must be a function'); |
| 155 | } |
| 156 | |
| 157 | let accumulator = initial; |
| 158 | |
| 159 | // Edge Case: Handle empty list |
| 160 | if (this.values.length === 0) { |
| 161 | return accumulator; |
| 162 | } |
| 163 | |
| 164 | for (const value of this.values) { |
| 165 | try { |
| 166 | accumulator = callback(accumulator, value); |
| 167 | } catch (error) { |
| 168 | // Edge Case: Handle errors in callback function |
| 169 | throw new Error(`Callback function error: ${error.message}`); |
| 170 | } |
| 171 | } |
| 172 | |
| 173 | return accumulator; |
| 57 | 174 | } |
| 58 | 175 | |
| 59 | 176 | /** |
| 60 | | * @param {(acc: any, el: any) => any} callback |
| 61 | | * @param {any} initial |
| 62 | | * @return {any} |
| 177 | * Folds the list from the right using a callback function. |
| 178 | * @param {(acc: any, el: any) => any} callback - Function to apply to each element. |
| 179 | * @param {any} initial - Initial accumulator value. |
| 180 | * @return {any} The final accumulator value. |
| 181 | * |
| 182 | * Handled Edge Cases: Empty list, callback function throwing errors |
| 63 | 183 | */ |
| 64 | 184 | foldr(callback, initial) { |
| 65 | | throw new Error('Remove this line and implement the function'); |
| 185 | // Edge Case: Handle when callback is not a function |
| 186 | if (typeof callback !== 'function') { |
| 187 | throw new Error('Callback must be a function'); |
| 188 | } |
| 189 | |
| 190 | let accumulator = initial; |
| 191 | |
| 192 | // Edge Case: Handle empty list |
| 193 | if (this.values.length === 0) { |
| 194 | return accumulator; |
| 195 | } |
| 196 | |
| 197 | // Process from right to left |
| 198 | for (let i = this.values.length - 1; i >= 0; i--) { |
| 199 | try { |
| 200 | accumulator = callback(accumulator, this.values[i]); |
| 201 | } catch (error) { |
| 202 | // Edge Case: Handle errors in callback function |
| 203 | throw new Error(`Callback function error: ${error.message}`); |
| 204 | } |
| 205 | } |
| 206 | |
| 207 | return accumulator; |
| 66 | 208 | } |
| 67 | 209 | |
| 68 | 210 | /** |
| 69 | | * @return {List} |
| 211 | * Reverses the list. |
| 212 | * @return {List} A new list with elements in reverse order. |
| 213 | * |
| 214 | * Handled Edge Cases: Empty list |
| 70 | 215 | */ |
| 71 | 216 | reverse() { |
| 72 | | throw new Error('Remove this line and implement the function'); |
| 217 | // Edge Case: Handle empty list |
| 218 | if (this.values.length === 0) { |
| 219 | return new List([]); |
| 220 | } |
| 221 | |
| 222 | const result = []; |
| 223 | for (let i = this.values.length - 1; i >= 0; i--) { |
| 224 | result.push(this.values[i]); |
| 225 | } |
| 226 | |
| 227 | return new List(result); |
| 73 | 228 | } |
| 74 | 229 | } |