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This article mainly explains "the example Analysis of interpret_cast in C++", interested friends may wish to have a look. The method introduced in this paper is simple, fast and practical. Next, let the editor take you to learn the "example Analysis of interpret_cast in C++".

With regard to the understanding of interpret_cast, some people will think that it is very powerful and can achieve fairly flexible type conversion. But we prefer to say that flexibility means high risk.

Let's first look at the following code:

Int number = 0x1234

Char* pc = interpret_cast (& number)

The purpose of this code is to decompose an integer into several bytes, and the result is stored in the character buffer pointed to by pc. The common shift operation is not used here, so the speed is very fast.

But how much do you think pc [0], pc [1], pc [2] and pc [3] are equal respectively?

The answer is not necessarily. To get the right answer, you need to consider at least the following two factors:

Is int 16-bit or 32-bit?

Is CPU large-end mode (Big-endian) or small-end mode (Little-endian)?

Only when all these are considered clearly can we get the right result. This is true for almost all interpret_cast. Not to mention the problems that can occur when code is migrated. I have a headache when I think about it.

Reinterpret_cast is essentially dependent on machines. To use reinterpret_cast safely, programmers must have a good understanding of the types involved and the conversion process implemented by the compiler. -C++Primer fifth edition

Another theory is that there is no free lunch.

But, but, but... Danger is danger, who can compare it with. Compared to C-style cast, interpret_cast must be better. Although the same unreasonable, but I made it clear that unlike C-style forced conversion, other people have to guess.

Of course, before you really use it, be sure to consider const_cast,static_cast, both of which are no longer applicable when using interpret_cast.

At this point, I believe that you have a deeper understanding of the "C++ interpret_cast example analysis", might as well come to the actual operation of it! Here is the website, more related content can enter the relevant channels to inquire, follow us, continue to learn!

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