README.md

@@ -9,21 +9,22 @@ A simple, educational C implementation of a dynamic array (vector-like) data str
 This library provides a basic dynamic array implementation in C, similar to C++'s `std::vector` or Python's lists. It demonstrates fundamental concepts in systems programming:
 
 - **Memory management** — allocation, reallocation, deallocation
-- **Generic programming** — using `void*` pointers  
+- **Generic programming** — type-agnostic macros that work with any pointer type
-- **Type-safe macros** — for type casting and operations
 - **Unit testing** — with the Unity C testing framework
+
 ## ✨ Features
 
-- **Dynamic resizing** — Automatically grows as elements are added
+- **Header-only** — just include `dynamic_array.h`, no compilation step needed
-- **Type-safe operations** — Macros for working with typed elements
+- **Dynamic resizing** — automatically grows as elements are added
-- **Simple API** — Easy-to-use functions for common operations
+- **Type-safe** — macros operate on typed pointers; direct indexing is fully typed
+- **Simple API** — a small set of macros for common operations
+
 ## 📁 Project Structure
 
 ```
-test-meson/
+dynamic_array/
 ├── src/
-│   ├── dynamic_array.c       # Implementation
+│   ├── dynamic_array.h       # Header-only implementation (public API)
-│   ├── dynamic_array.h       # Public API header
 │   ├── test_dynamic_array.c  # Unit tests
 │   └── CMakeLists.txt        # Build configuration
 ├── submodules/
@@ -33,6 +34,7 @@ test-meson/
 ├── Makefile                  # Build automation
 └── README.md                 # This file
 ```
+
 ## 🔧 Prerequisites
 
 **Linux-only project**
@@ -41,6 +43,7 @@ test-meson/
 - **C compiler** (GCC recommended, Clang supported)
 - **Make** (optional, but recommended)
 - **build-essential** (on Ubuntu/Debian): `sudo apt-get install build-essential`
+
 ## 🔨 Building
 
 ### Using the Makefile (Recommended)
@@ -63,6 +66,7 @@ ctest --output-on-failure
 cmake --install .
 cd .. && rm -rf build
 ```
+
 ## 💡 Usage
 
 ### Including the Library
@@ -70,72 +74,70 @@ cd .. && rm -rf build
 ```c
 #include "dynamic_array.h"
 
-// Create an array of integers
+// Create a typed array (works with any pointer type)
-ArrayCreateOptions opts = {
+int *arr = NULL;
-    .initial_size = 10,
+array_create(arr);
-    .element_size = sizeof(int)
-};
-Array *my_array = array_create(&opts);
 
 // Add elements
-int value = 42;
+array_push_value(arr, 10);
-array_set_value(my_array, 0, &value);
+array_push_value(arr, 20);
+array_push_value(arr, 30);
 
-// Retrieve elements
+// Access elements directly via indexing
-int *retrieved = (int*)array_get_value(my_array, 0);
+int first = arr[0]; // 10
 
-// Using type-safe macros
+// Remove the last element
-int result = array_set_value_as(int, my_array, 1, 100);
+array_pop(arr);
 
-// Get size and capacity
+// Inspect size and capacity via the header
-size_t size = array_get_size(my_array);
+const ArrayHeader *header = array_get_header(arr);
-size_t capacity = array_get_capacity(my_array);
+size_t size     = header->size;     // current number of elements
+size_t capacity = header->capacity; // allocated capacity
 
 // Cleanup
-array_deconstructor(&my_array);
+array_destroy(arr); // frees memory and sets arr to NULL
 ```
+
 ## 📖 API Reference
 
 ### Structures
 
-#### `Array`
+#### `ArrayHeader`
+
+Stored immediately before the array data in memory. Retrieve it with `array_get_header`.
 
 ```c
 typedef struct {
-    void *value;           // Pointer to element data
-    size_t element_size;   // Size of each element
     size_t size;      // Current number of elements
     size_t capacity;  // Allocated capacity
-} Array;
+} ArrayHeader;
 ```
 
-#### `ArrayCreateOptions`
+Memory layout:
 
-```c
-typedef struct {
-    int initial_size;      // Initial capacity
-    size_t element_size;   // Size of each element type
-} ArrayCreateOptions;
 ```
-
+[ ArrayHeader | elem 0 | elem 1 | ... ]
-### Functions
+               ↑
-
+               pointer returned by array_create (and all macros)
-| Function | Description |
+```
-|----------|-------------|
-| `Array *array_create(const ArrayCreateOptions *options)` | Creates a new dynamic array |
-| `void array_deconstructor(Array **pp_array)` | Frees allocated memory and sets pointer to NULL |
-| `void array_resize(Array *p_array, size_t new_size)` | Resizes the array's capacity |
-| `void *array_get_value(const Array *p_array, size_t index)` | Retrieves a pointer to the element at index |
-| `void array_set_value(Array *p_array, size_t index, const void *value)` | Sets the element at index |
-| `size_t array_get_size(const Array *p_array)` | Returns the current number of elements |
-| `size_t array_get_capacity(const Array *p_array)` | Returns the allocated capacity |
 
 ### Macros
 
 | Macro | Description |
 |-------|-------------|
-| `array_get_value_as(type, arr, idx)` | Type-safe retrieval of elements |
+| `array_create(arr)` | Allocates a new array; sets `arr` to point to the first element |
-| `array_set_value_as(type, arr, idx, value)` | Type-safe setting of elements (with type checking) |
+| `array_destroy(arr)` | Frees the array and sets `arr` to `NULL` |
+| `array_get_header(arr)` | Returns a pointer to the `ArrayHeader` for `arr` |
+| `array_push_value(arr, value)` | Appends `value`; grows the array automatically if needed |
+| `array_pop(arr)` | Removes the last element by decrementing `size` |
+
+### Constants
+
+| Constant | Default | Description |
+|----------|---------|-------------|
+| `DYNAMIC_ARRAY_DEFAULT_ARRAY_SIZE` | `10` | Initial capacity allocated by `array_create` |
+| `DYNAMIC_ARRAY_CAPACITY_FACTOR` | `2` | Growth multiplier applied on resize |
+
 ## ✅ Testing
 
 Tests are written using the [Unity](http://www.throwtheswitch.org/unity) C testing framework.
@@ -149,6 +151,7 @@ Or directly with ctest:
 ```bash
 cd build && ctest --output-on-failure
 ```
+
 ## 📦 Installation
 
 ### Default Installation
@@ -158,7 +161,6 @@ make install
 ```
 
 This installs to `~/.local/bin/dynamic_array/`:
-- **Library:** `lib/libdynamic_array.a`
 - **Header:** `include/dynamic_array.h`
 
 ### Custom Installation Directory
@@ -173,20 +175,26 @@ Or set it as an environment variable:
 export INSTALL_PREFIX=$HOME/.local
 make install
 ```
+
 ## ⚠️ Known Issues & Limitations
 
-- ⚠️ No bounds checking in release builds
+- ⚠️ No bounds checking
+- ⚠️ `array_pop` does not return the removed element (use `arr[header->size - 1]` before popping)
 - ⚠️ Simple reallocation strategy (not optimized for performance)
 - ⚠️ Not thread-safe
-- ⚠️ Limited error handling
+- ⚠️ `realloc` failure is not propagated to the caller
 - ⚠️ Educational purpose only — use established libraries for production
+
 ## 🚀 Future Improvements
 
+- [ ] Return value from `array_pop`
+- [ ] Propagate allocation failures
 - [ ] Add more comprehensive error handling
-- [ ] Implement shrinking functionality
+- [ ] Implement shrinking / `array_reserve`
 - [ ] Add iterator support
 - [ ] Optimize memory allocation strategy
 - [ ] Add more test coverage
+
 ## 📄 License
 
 This project is for educational purposes.