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()?

The square roots of the integers from 1 to 100, Assume we wish to partition...

Assume we wish to partition the square roots of the integers from 1 to 100 in to two piles of fifty numbers every, such that the sum of the numbers in the first pile is as close as

Compiler design-limit the methods, Ask question #Minimum 100Problem : Compi...

Ask question #Minimum 100Problem : Compiler Design - Limit the methods Rahul is a newbie to the programming and while learning the programming language he came to know the followi

C program to check factorial, C Program to check FACTORIAL   main() ...

C Program to check FACTORIAL   main() {             int i,j,m,fact,sum=0;           clrscr();           printf("ENTER THE NO.: ");           scanf("%d",&m);

Padovan string, A Padovan string P(n) for a natural number n is defined as:...

A Padovan string P(n) for a natural number n is defined as: P(0) = ‘X’ P(1) = ‘Y’ P(2) = ‘Z’ P(n) = P(n-2) + P(n-3), n>2 where + denotes string concate program 1 : package test

Recursion, Solve the Nine Queens problem recursively. The objective is to p...

Solve the Nine Queens problem recursively. The objective is to place nine queens on an empty chessboard so that no queen is “attacking” any other, i.e., no two queens are in the sa

Flowcharting, how to create a flowchart? can you help me in my assignment a...

how to create a flowchart? can you help me in my assignment about flowcharting ....

Decode the code, Smugglers are becoming very smart day by day. Now they hav...

Smugglers are becoming very smart day by day. Now they have developed a new technique of sending their messages from one smuggler to another. In their new technology, they are send

Explain about the constants in c language, Explain about the Constants in c...

Explain about the Constants in c language? The Constants in C refer to fixed values that don't change during the execution of a program. C has four fundamental types of constan

Virtual constructor, Is it possible to have Virtual Constructor? If yes, ho...

Is it possible to have Virtual Constructor? If yes, how? If not, Why not possible?

Area under curve, write a program to find the area under the curve y=f(x) b...

write a program to find the area under the curve y=f(x) between x=a and x=b integrate y=f(x)   #include float start_point, /* GLOBAL VARIABLES */

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