I. Possible combinations:
(1) const char * P
(2) Char const * P
(3) char * const P(4) const char ** P
(5) Char const ** P
(6) char * const * P
(7) Char ** const P
Of course, there are several cases of inserting a const in (5), (6), and
One, possible combinations:(1) Const CHAR*P(2) Char Const*p(3) Char *const p(4) const char **P(5) Char Const**p(6) Char *const *p(7) Char **const pOf course, in (5), (6), (7) and then insert a const in a number of cases, but the analysis of the
Use const whenever possible
One wonderful thing about const is that it allows you to specify a semantic constraint: a specific object should not be modified. The compiler will execute this constraint. It allows you to notify the compiler and other
Const T, const T *, T * const, const T &, const T * & difference, const
Here T refers to a data type, which can be basic data types such as int, long, and doule, or class of its own type. A single const must be a constant, but are you confused
Constraints for assigning values according to ansi c:
1. Both operands are pointers to compatible types with or without delimiters.
2. the type pointed to by the Left pointer must have all the qualifiers of the type pointed to by the right
The use of const in C + + is very extensive, different location to use the meaning is not the same, so want to write an article to make a summary.
First of all, it is clear that the const is the basic meaning of "unchanging", but the same does not
Item 3: Use const whenever possible
By Scott Meyers
Translator: fatalerror99 (itepub's nirvana)
Release: http://blog.csdn.net/fatalerror99/
One wonderful thing about const is that it allows you to specify a semantic (semantic) Constraint: a specific
Const thinking
1. What is const?A common type is a type described by the Type modifier Const. The values of variables or objects of a common type cannot be updated. (Of course, we can steal the bar for updating :)
2. Why is const introduced?The
1. Defining constants(1) The const modifier variable, the following two kinds of definition form are essentially the same. It means that the variable value of the type with the Const modifier is immutable.
TYPE const VALUENAME = value;
Const is the abbreviation of constant, the meaning of "constant unchanged". The const-modified items are protected against accidental changes and can improve the robustness of the program. So many C + + programming books suggest: "Use const whenever
Const is used to declare a constant, and when you do not want a value to be changed, use the const,const INT max && int const Max is no different, all can.Does not involve pointer const very well understood.Cases involving pointers:Conat int b=100,
Effective C + + Chapter 1. Make yourself accustomed to C + + (Accustoming yourself to C + +) Item 3. Use const (using const whenever possible) whenever possible1. Const and semantic constraintsconst allows you to specify a semantic constraint (that
The use of const in C + + is very wide, the meaning of the use of different locations is not the same, so want to write an article to do a summary. First, it is clear that const is the basic meaning of "unchanging", but it does not mean that
1. What is const?
A common type is a type described by the Type modifier Const. a variable or object Value of a common type cannot be updated.
. (Of course, we can steal the bar for updating :)
2. Why is const introduced?
The initial purpose
Const Usage Details
Object-oriented is an important feature of C ++.However, the optimizations added by C ++ on the basis of C are also very dazzling.Const can directly replace # define in C.The following points are very important, and the
Object-oriented is an important feature of C ++.
However, the optimizations added by C ++ on the basis of C are also very dazzling.
Const can directly replace # define in C.
The following points are very important, and the consequences are also very
Attention
Const object implicitly feels the local variable of the file
When a non-const variable is defined in the global scope , it can be visited throughout the program. We can define a non-const variable in a file, and if the
Pay attention to this point
Const object defaults to a local variable of the file
When defining a non-const variable in the global scope , it can be accessed throughout the program, and we can define a non-const variable in a file,
In the program often encountered the const, but he did not know very well, today saw an article is very good, so copied over ....Original link: http://blog.csdn.net/Eric_Jo/article/details/4138548The use of the Const keyword in C + + is very
C + + In the use of the Const keyword is very flexible, and using the const will greatly improve the robustness of the program, I based on all aspects of the information to summarize the following, I hope to help friends.
Const is a commonly used
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