Key points of this article:1, try to replace Pass-by-value with Pass-by-reference-to-const. The former is more efficient and can avoid cutting problems.2. This rule does not apply to both the built-in type and the iterator and function object types
First of all, theparameters of all functions in JavaScript are passed by value! There is no pass by reference! in speaking of passing Parameters let's start with pointers. Learn the C pointer should know that the pointer variable is stored in an
"Effective C + +"Clause 20: Prefer to replace pass-by-value with Pass-by-reference-to-constBy default, C + + passes an object to a function by value. Unless you know otherwise, the function parameter is the initial value of the copy of the actual
clause 20: Prefer to replace pass-by-value with Pass-by-reference-to-const
By default, C + + passes objects to (or from) functions in by value, a way that inherits from C. Unless you specify otherwise, the function arguments are based on the actual
Effective C + + ' ning to pass-by-reference-to-const replace Pass-by-value 'By default, C + + passes an object to a function by value (a way that inherits from C). Unless you specify otherwise, the function parameter is the initial value of the
Effective C + + ' ning to pass-by-reference-to-const replace Pass-by-value 'By default, C + + passes an object to a function by value (a way that inherits from C). Unless you specify otherwise, the function parameter is the initial value of the
Key points:
Try to replace pass-by-reference-to-const with pass-by-value. This is usually more efficient and avoids the problem of object cutting when the subclass object is copied to the base class.
Pass-by-value should be used for the internal
(1)
If the pass-by-value parameter is passed when a function is called, the function parameters take the actual copy of the real parameter as the initial value, and the call end obtains a replica of the function return value.
See the following code:
By default, C ++ uses the by Value Method to pass objects to functions. The real parameters of a function are all based on the response of the actual parameter as the initial value, and the call end obtains a replica of the function return value.
By default, C ++ uses the by Value Method to pass the object (or from) function. The function parameter is the initial value of the copy of the real parameter, and the result obtained by the function is also a copy of the function return value.
Preface:We've all used the value-passing method of C, so how does the value transfer work in C + + cases?Like what:int foo (int x); int I;foo (i);1. Get a copy of I within the program2. Passing a copy to the Foo function3.foo backThese replicas are
Remember:
Replace Pass-by-value with Pass-by-reference-to-const as much as possible. The former is usually more efficient and avoids cutting problems (slicing problem).
The above rules do not apply to built-in types, as well as STL
Replace Pass-by-value with Pass-by-reference-to-const as much as possible. The former is usually more efficient because it avoids the call to copy constructors and destructors, and avoids cutting problems.is a good example of slicing problems:
Read a post on the internet to explain the value of Java and pass by reference, feel quite comprehensive, turn around, for later study reference:1: What is passed by valueRefers to when a method call passes a parameter that is passed by a copy of
The day before yesterday when the system was in the Java parameter Transfer problem card, looking back to the relevant information, the parameter transfer problem has a new understanding and mastery, but there is a problem is still very vague, is
The day before yesterday when the system was in the Java parameter Transfer problem card, looking back to the relevant information, the parameter transfer problem has a new understanding and mastery, but there is a problem is still very vague, is
This is a much-discussed topic in the Java field. However, so far I have found that many people have not figured it out (including myself, of course ). Until I read this articleArticle"Does Java pass by reference or pass by value? .
From this, I
A detailed description of value passing and reference passing:1: what is passed by valueRefers to when a method call passes a parameter that is passed by a copy of the Value. Examples are as Follows:[java]View PlainCopy
Public class
Warning: Call-time pass-by-reference has been deprecated in E: \ Program Files \ EasyPHP 3.0 \ www \ bugfree \ Include \ Class \ XmlParse. class. php on line 46
Warning: Call-time pass-by-reference has been deprecated in E: \ Program Files \ EasyPHP
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