Ecosyste.ms: Awesome

An open API service indexing awesome lists of open source software.

Awesome Lists | Featured Topics | Projects

https://github.com/willbrennan/learn_stl

Learning how the C++ Standard Library works; by implementation
https://github.com/willbrennan/learn_stl

cpp cpp-course cpp-library cpp17 learning-by-doing learning-cplusplus

Last synced: 2 months ago
JSON representation

Learning how the C++ Standard Library works; by implementation

Awesome Lists containing this project

README 

        
# Learn STL

### Learning about the C++ Standard Library by Implementation

Ever wondered how std::tuple is implemented? How std::get works? Well I started implementing this to find out just that.



The standard library heavily relies on many [C++ Idioms](https://en.wikibooks.org/wiki/More_C%2B%2B_Idioms) and unusual language features, by implementing the library you can get a bit more familiar with them!



Each of the components have documentation in *[/docs](https://github.com/WillBrennan/learn_stl/tree/master/docs)* explaining how they work, what idioms the use, and whats interesting about them. 



Hopefully you'll find this an interesting read!



Feel free to submit a PR adding more components or improving library / documentation!



### Vocab Types

#### [`any`](https://github.com/WillBrennan/learn_stl/blob/master/docs/any.md)

Any is the de-facto type-erasure method in C++, it provides type-safe container for single values of any type. The implementation provides an introduction to polymorphism in C++.



#### [`optional`](https://github.com/WillBrennan/learn_stl/blob/master/docs/optional.md)

How can you store an object without a default-constructor on the stack? Well with a `union` is how, but what is this weird special type.



#### [`tuple`](https://github.com/WillBrennan/learn_stl/blob/master/docs/tuple.md)

Tuple heavily depends on variadic templates and `std::index_sequence`, and isn't obvious how its implemented. It's a refreshing look at 

features which aren't used day-to-day.



#### [`variant`](https://github.com/WillBrennan/learn_stl/blob/master/docs/variant.md)

Another component thats heavily dependent on variadic templates, it employs more template metaprogramming tricks than `tuple`. It also provides an interesting use case of `aligned_storage`.



### Containers

#### [`array`](https://github.com/WillBrennan/learn_stl/blob/master/docs/array.md)

Array is deceptively simple, but how are its constructors and destructors implicity declared? Why is array constexpr but vector isn't, and what is aggregate-initialization?

Understanding Array requires a strong comprehension of these often over-looked language features.



#### [`vector`](https://github.com/WillBrennan/learn_stl/blob/master/docs/vector.md)

Everyone knows `std::vector` right? But why is reserving so important? And what is `std::allocator` and why wrap it in `std::allocator_traits`?



#### [`valarray`](https://github.com/WillBrennan/learn_stl/blob/master/docs/valarray.md)

`valarray` provides an introduction to expression-templates. It stores elements in a vector, and it provides element-wise unary and binary operations. It won't create any temporaries and will only perform one iteration as it evaluates the expression for each resultant element.



### Memory Mangement

#### [`unique_ptr`](https://github.com/WillBrennan/learn_stl/blob/master/docs/memory.md#unique_ptr)

`unique_ptr` is pretty simple, but its always good to understand what `std::default_deleter` does and how dangerous aggregate initialisation can be



#### [`addressof`](https://github.com/WillBrennan/learn_stl/blob/master/docs/memory.md#addressof)

`addressof` might seem like a verbose way of calling `&T`; but why does it exist? And why is it constexpr in C++17 and what does a constexpr pointer mean? 



#### [`allocator`](https://github.com/WillBrennan/learn_stl/blob/master/docs/memory.md#allocator)

`allocator` is relatively simple, but why does it define `is_always_equal` and `propagate_on_container_move_assignment`.