Archive for category: Templates

AutomaticReturnType

Automatic Return Type (C++98)

October 15, 2021

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Depending on the used C++ standard, there are different ways to return the correct return type of a function…

templates

Dependent Names

October 7, 2021

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A dependent name is essentially a name that depends on a template parameter. A dependent name can be…

templates

The Special Friendship of Templates

September 29, 2021

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A friend has unrestricted access to the members of a class. Consequently, friendship should be given…

templates

Visiting a std::variant with the Overload Pattern

September 23, 2021

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Typically, you use the overload pattern for a std::variant. std::variant is a type-safe union. A std::variant…

templates

Smart Tricks with Parameter Packs and Fold Expressions

September 16, 2021

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To complete my post about variadic templates and fold expressions, I present in this post smart tricks…

templates

From Variadic Templates to Fold Expressions

September 8, 2021

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In my last two posts, "Variadic Templates or the Power of Three Dots" and "More about Variadic Templates",…

templates

More about Variadic Templates …

August 13, 2021

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There is a lot of power in the strange-looking three dots that are heavily used in the Standard Template…

templates

Variadic Templates or the Power of Three Dots

August 6, 2021

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A variadic template is a template that can have an arbitrary number of template parameters. If you see…

templatesInstantiation

Template Instantiation

July 29, 2021

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Template instantiation is creating a concrete function or a concrete class out of a function or class…

TemplateSpecialization

Full Specialization of Function Templates

July 9, 2021

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As you may know from my previous post, Template Specialization, a function template can only be full…

Latest news

std::executionNovember 18, 2024 - 9:03 am
std::execution, previously known as executors or Senders/Receivers, provides “a Standard C++ framework for managing asynchronous execution on generic execution resources“. (P2300R10) Side Note Change of plans. My original plan was to present the C++26 library after the core language. However, the implementation status of the library is not good enough. Therefore, I decided to continue […]
C++26 Core Language: Small ImprovementsNovember 4, 2024 - 8:34 am
There are more small improvements in the C++26 language, which you should know. static_assert extension First, here’s the syntax of static_assert in C++11: static_assert(compile time predicate, unevaluated string) With C++26, the string can be a user-defined type having the following properties: static_assert can now be used with a format string. Here’s a nice example from […]
Placeholders and Extended Character SetOctober 28, 2024 - 10:19 am
Placeholders are a nice way to highlight variables that are no longer needed. Additionally, the character set of C++26 will be extended. Placeholders Structured bindings are a C++17 feature that allows you to bind multiple variables to the elements of a structured object. The following program demonstrates using tuples and structured bindings to return and […]
Contracts in C++26October 21, 2024 - 9:54 am
Contracts allow you to specify preconditions, postconditions, and invariants for functions. Contracts should already be part of C++20 but were removed in the standard meeting in Cologne. Here is what Herb Sutter said about contracts on Sutter’s Mill: “contracts is the most impactful feature of C++20 so far, and arguably the most impactful feature we […]
Reflection in C++26: Determine the LayoutOctober 14, 2024 - 9:42 am
Thanks to reflection, you can determine the layout of types. My examples are based on the reflection proposal P2996R5. Class Layout The following program determines the class layout of a few members. // classLayout.cpp #include <experimental/meta> #include <iostream> #include <utility> #include <vector> #include <array> struct member_descriptor { std::size_t offset; std::size_t size; bool operator==(member_descriptor const&) const […]
Reflection in C++26: Metafunctions for Enums and ClassesOctober 7, 2024 - 1:53 pm
Today, I continue my journey through reflection in C++26 and play with enums and classes. The names of the metafunctions to access an Enum or a Class member are often identical. Access the Members of an Enum The following program is based on one by Daveed Vandevoorde. Daveed is one of the fathers of reflection, […]