Do i have to check for null after p = new fred()?, C/C++ Programming

Assignment Help:

A: No. (Excluding if you have an old compiler, you might have to force the new operator to throw an exception if it runs out of memory.)

This turns out to be a real pain to always write down explicit NULL tests after each new allocation. Code like the following is extremely tedious:

Fred* p = new Fred();

if (p == NULL)

throw std::bad_alloc();

If your compiler doesn't support (or if you reject to use) exceptions, your code may be even more tedious:

Fred* p = new Fred();

if (p == NULL) {

std::cerr << "Couldn't allocate memory for Fred" << std::endl;

abort();

}

In C++, if the runtime system can't allocate sizeof(Fred) bytes of memory throughout p

= new Fred(), a std::bad_alloc exception will thrown. Unlike malloc(), new never returns

NULL!

Then you should simply write:

Fred* p = new Fred(); // No require to check if p is NULL

Though, if your compiler is old, it might not yet support this. Determine by checking your compiler's documentation under "new". If you hold an old compiler, you might have to force the compiler to have this behavior.

 

Note: If you are using Microsoft Visual C++, to obtain new to throw an exception while it fails you have to #include some standard header in at least one of your .cpp files. For instance, you could

#include (or or or ...).

 

 


Related Discussions:- Do i have to check for null after p = new fred()?

Program, fine the class bankAccount to implement the basic properties of a ...

fine the class bankAccount to implement the basic properties of a bank account. An object of this class should store the following data: Account holder''s name (string), account nu

Write down the code for binary search tree in c++?, A: BinarySearchTree.h ...

A: BinarySearchTree.h ---------------------- #ifndef BINARY_SEARCH_TREE_H_ #define BINARY_SEARCH_TREE_H_ #include "dsexceptions.h" #include // For NULL // Binary

How virtual functions can be implemented in c++?, Normal 0 fals...

Normal 0 false false false EN-US X-NONE X-NONE

Palindrome, A palindrome is a string that reads the same from both the ends...

A palindrome is a string that reads the same from both the ends. Given a string S convert it to a palindrome by doing character replacement. Your task is to convert S to palindrome

What is the difference between structure and class, What is the difference ...

What is the difference between structure and class? - Members of structures are public while those of a class are private. - Classes provide data hiding while structures don

C++ multiplayer game programming project, C++ Multiplayer Game Programming ...

C++ Multiplayer Game Programming Project Project Description: We are seeking an experienced C++ Game Programmer to enhance clientside related aspects of MCS: Mars City Securi

Super ansii prgm, Ask quIn the Byteland country a string "s" is said to sup...

Ask quIn the Byteland country a string "s" is said to super ascii string if and only if count of each charecter in the string is equal to its ascci value in the byteland country as

Padovan string, write a C program for padovan string for a natural number

write a C program for padovan string for a natural number

Inheitance, ambiguity in multiple inheritance

ambiguity in multiple inheritance

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd