Tag Archives: advanced-c++

Ordering by constraints

In the previous post we have seen how constraint conjunction and disjunction works, and how a function template with constraints is a better match than a function template without constraints (provided that the constraints are satisfied) when determining the best … Continue reading

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Requires-clause — updated

The previous post, “Requires-clause”, contained incorrect information about parentheses inside a requires-clause. Token || inside parentheses is still interpretted as a disjunction of two constraints. I apologize for misleading the readers. I also want to thank James Pfeffer for bringing … Continue reading

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Requires-clause

Update. This post in its original form contained incorrect information about the meaning of parentheses inside requires-clauses in section Conjunction and Disjunction. The section has now been changed to correct this. The updated text is in blueish color. Even if … Continue reading

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Short-circuiting in meta-functions

Short-circuiting in logical operations is a very useful and an often used feature: Should cond_a() evaluate to false, cond_b() is guaranteed not to be evaluated. This is useful for two reasons. One is performance: if cond_b() is an expensive operation … Continue reading

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Faces of undefined behavior

I have been busy recently (doing C++-related stuff) and cannot find a spare time for preparing a decent blog post. I expect that to change in November. For the interim I am posting here my last year’s talk at code::dive: … Continue reading

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A friendly type predicate

This is a sequel to the previous post on writing a custom type predicate. One of the readers on Reddit made a very insightful observation. The user has implemented a type that she intends to use with our library, call … Continue reading

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Your own type predicate

In this post we will see how to define a type trait or a type predicate or a meta-function that would allow us to check at compile time whether a type exposes an interface that we need. That is, we … Continue reading

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Compile-time string concatenation

We will start with a bug, taken from real life. It spans across three files: Question: what happens when this program is executed?

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Asserts in constexpr functions

Assertions (like C-style macro assert) are not an ideal, but still useful tool for indicating assumptions about program correctness, and help finding programmer bugs. In this post we will see how we can use assertions in constexpr functions. This works … Continue reading

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