Tag Archives: type system

String’s competing constructors

Let’s start with the problem. I want to check whether a program received a text message that consists of four consecutive zeroes. Not ‘0’, but the numeric zero. I will create a constant std::string representing the special sequence and compare … 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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Toggles in functions

Have you ever seen a function call like this? We are processing something: this should be clear from the context. But what do these parameters mean? What is true and what is false? From the function call we will never … Continue reading

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More const — fewer bugs

I have just read article “Please declare your variables as const” by Bartłomiej Filipek. It argues that declaring your variables const is beneficial for reasons other than performance. In particular, it can help find bugs in your code. Now, let … Continue reading

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Another polymorphism

In this post we will try to see by a practical example what Boost.Variant is for. You can sometimes see examples that use type variant<int, double, string>, but to me they are artificial: I never needed to use something that … Continue reading

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