Questions tagged [constant-expression]
Use this whenever compile-time expression is implemented (currently exists in C++ and D). Do not use this tag if the compile-time evaluation property is achieved through template metaprogramming in C++ (in which case use the [template-meta-programming] tag).
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Row-sparse constexpr 2D array, generated at compile-time from array coordinate/value entries
The goal of the code is to enable me to express a 2D array in an unsorted coordinate-sparse representation in my code (i.e. a list of individual x, y, value entries ...
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Enabling bitset-like behavior for enum classes (C++20)
I want to enable bitmask-like behavior (ie. overloaded operator|, operator& and operator^...
5
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483
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Compile-time Matrix Class
Intended as a small project to test out various C++20 features, as well as learn a little bit more about matrices and their uses, I decided to implement a relatively simple matrix class.
After ...
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1
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Compiletime (constexpr) Differential Equation System Description for use in Optimal Control
Background
In the field of optimal control, it is part of everyday business to solve ordinary differential equations numerically. A differential equation system or dynamic system describes e.g. the ...
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constexpr hash function
Here's a constexpr hash function, that will pack a string into the largest unsigned integral type available. So, what do you think?
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Two constexpr ceil functions
ceil_constexpr is is based on: https://stackoverflow.com/questions/8377412/ceil-function-how-can-we-implement-it-ourselves/8378022#8378022
ceil_constexpr2 is a simpler version that takes advantage of ...
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1
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type erased pointer to member function callable and SFINAE [closed]
I'm implementing a std::function like class that uses type erasure.
So far it can be used with function objects (functions/function pointers, functors, lamdas) and pointer to member function.
But to ...
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2
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1
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370
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Flatten 2d-array at compiletime
In my code, I need to flatten a two-dimensional std::array into a one-dimensional one at compile time. While writing the code I realized, that I am unsure about ...
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C++ ring buffer using some C++ 17 and coming C++ 20 std::span
When I heard about the new Linux I/O interface io_uring I searched about the ring buffer.
I then thought I may replace my safe queue which is base on C++ 11 ...
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6
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1
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A cartesian product of tuples in C++17
I would like to write a function that computes a cartesian product of two tuples in C++17 (the tuples can be of type std::tuple or ...
3
votes
1
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Simple DP problem solved in compile time
The problem is taken from one of recent SO questions:
Finding max sum of matrix elements with following constraints:
Exactly one row element has to be included in the sum
If element at (i, j) is ...
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C++ compile time counter/accumulator [closed]
I could not find a compile time counter/accumulator to achieve something like the following:
...
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Check array contains element at compile time
We have a modifyCoefficient(const char* name, int value) function that updates the value of a coefficient in a container. The names are known at compile time, they ...
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Constexpr unit tests and asserts
I'm trying out some different programming styles to experiment with the new C++ concepts. Within the experiment I was looking into how constexpr could be helpful ...
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0
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682
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constexpr hashtable string to user type
This creates something like constexpr mar<String, T> using C++14.
Collision resolution is with static_assert and manually ...
- 1,490
12
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User defined literal for std::integral_constant
I created a user defined literal _c to convert an "integer" literal into an std::integral_constant. Basically, the goal is to ...
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