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What is the reason for avoiding using macros to define constants or functions in C++? for this problem, this article introduces the corresponding analysis and solutions in detail, hoping to help more partners who want to solve this problem to find a more simple and feasible way.

ES.31: do not use macros to define constants or functions

Reason (reason)

Macros are a major source of bugs. Macros don't obey the usual scope and type rules. Macros don't obey the usual rules for argument passing. Macros ensure that the human reader sees something different from what the compiler sees. Macros complicate tool building.

Macros are one of the main sources of errors. Macros do not follow the usual scope and type guidelines. Macros also do not follow parameter-passing guidelines. Macros provide people with a perspective that is somewhat different from the compiler perspective. Macros make tool construction more complex.

Example, bad (negative example)

# define PI 3.14#define SQUARE (a, b) (a * b)

Even if we hadn't left a well-known bug in SQUARE there are much better behaved alternatives; for example:

Although there are no known errors in the SQUARE definition, there are other options that can work better.

Constexpr double pi = 3.14

Template T square (T a, T b) {return a * b;}

The answer to the question about why C++ avoids using macros to define constants or functions is shared here. I hope the above content can be of some help to you, if you still have a lot of doubts to be solved. You can follow the industry information channel for more related knowledge.

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