docs/src/features.md

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185 You do not always need all fields in the iterator structure, depending on your use case. 185 You do not always need all fields in the iterator structure, depending on your use case.
186 Sometimes you only need the `index` (for example when iterating over simple lists), and other times you will need the 186 Sometimes you only need the `index` (for example when iterating over simple lists), and other times you will need the
187 `slot` and `kv_data` fields (for example when iterating over maps). 187 `slot` and `kv_data` fields (for example when iterating over maps).
188 188
189 If the predefined fields are insufficient for your use case, you can alternatively create your own iterator structure 189 If the predefined fields are insufficient for your use case, you can alternatively create your own iterator structure
190 and place the `CX_ITERATOR_BASE` macro inside. 190 and place the `CX_ITERATOR_BASE` macro as first member of that structure.
191 191
192 Usually an iterator is not mutating the collection it is iterating over. 192 Usually an iterator is not mutating the collection it is iterating over.
193 In some programming languages it is even disallowed to change the collection while iterating with foreach. 193 In some programming languages it is even disallowed to change the collection while iterating with foreach.
194 But sometimes it is desirable to remove an element from the collection while iterating over it. 194 But sometimes it is desirable to remove an element from the collection while iterating over it.
195 For this purpose, most collections allow the creation of a _mutating_ iterator. 195 For this purpose, most collections allow the creation of a _mutating_ iterator.
202 202
203 *Header file:* [collection.h](api/collection_8h.html) 203 *Header file:* [collection.h](api/collection_8h.html)
204 204
205 Collections in UCX 3 have several common features. 205 Collections in UCX 3 have several common features.
206 If you want to implement an own collection data type that uses the same features, you can use the 206 If you want to implement an own collection data type that uses the same features, you can use the
207 `CX_COLLECTION_MEMBERS` macro at the beginning of your struct to roll out all members a usual UCX collection has. 207 `CX_COLLECTION_BASE` macro at the beginning of your struct to roll out all members a usual UCX collection has.
208 ```c 208 ```c
209 struct my_fancy_collection_s { 209 struct my_fancy_collection_s {
210 CX_COLLECTION_MEMBERS 210 CX_COLLECTION_BASE;
211 struct my_collection_data_s *data; 211 struct my_collection_data_s *data;
212 }; 212 };
213 ``` 213 ```
214 Based on this structure, this header provides some convenience macros for invoking the destructor functions 214 Based on this structure, this header provides some convenience macros for invoking the destructor functions
215 that are part of the basic collection members. 215 that are part of the basic collection members.
223 223
224 ## List 224 ## List
225 225
226 *Header file:* [list.h](api/list_8h.html) 226 *Header file:* [list.h](api/list_8h.html)
227 227
228 This header defines a common interface for all list implementations, which is basically as simple as the following 228 This header defines a common interface for all list implementations.
229 structure. 229
230 ```c 230 UCX already comes with two common list implementations (linked list and array list) that should cover most use cases.
231 struct cx_list_s { 231 But if you feel the need to implement an own list, the only thing you need to do is to define a struct with a
232 CX_COLLECTION_MEMBERS // size, capacity, etc. 232 `struct cx_list_s` as first member, and set an appropriate list class that implements the functionality.
233 cx_list_class const *cl; // The list class definition
234 };
235 ```
236 The actual structure contains one more class pointer that is used when wrapping a list into a pointer-aware list
237 with `cxListStorePointers()`. What this means, is that - if you want to implement your own list structure - you
238 only need to cover the case where the list is storing copies of your objects.
239
240 UCX comes with two common list implementations (linked list and array list) that should cover most use cases.
241 But if you feel the need to implement an own list, the only thing you need to do is to define a struct where
242 `struct cx_list_s`, and set an appropriate list class that implements the functionality.
243 It is strongly recommended that this class is shared among all instances of the same list type, because otherwise 233 It is strongly recommended that this class is shared among all instances of the same list type, because otherwise
244 the `cxListCompare` function cannot use the optimized implementation of your class and will instead fall back to 234 the `cxListCompare` function cannot use the optimized implementation of your class and will instead fall back to
245 using iterators to compare the contents element-wise. 235 using iterators to compare the contents element-wise.
246 236
247 ### Linked List 237 ### Linked List

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