Defines a macro, Computer Engineering

Assignment Help:

Defines a macro

Defines a macro with the given name, having as its value the given replacement text. After that (for the rest of the current source file), wherever the preprocessor sees that name, it will replace it with the replacement text. The name follows the same rules as ordinary identifiers (it can contain only letters, digits, and underscores, and may not begin with a digit). Since macros behave quite differently from normal variables (or functions), it is customary to give them names which are all capital letters (or at least which begin with a capital letter). The replacement text can be absolutely anything--it's not restricted to numbers, or simple strings, or anything.

The most common use for macros is to propagate various constants around and to make them more self-documenting. We've been saying things like

char line[100];

...

getline(line, 100);

but this is neither readable nor reliable; it's not necessarily obvious what all those 100's scattered around the program are, and if we ever decide that 100 is too small for the size of the array to hold lines, we'll have to remember to change the number in two (or more) places.

A much better solution is to use a macro:

#define MAXLINE 100 char line[MAXLINE];

...

getline(line, MAXLINE);

 


Related Discussions:- Defines a macro

Default communicator in mpi, Problem 1 (a) What is the difference betw...

Problem 1 (a) What is the difference between an MPI blocking send function and an MPI non-blocking send function? (b) What is a communicator in MPI? (c) Name correctly

Goals - artificial intelligence, Goals - artificial intelligence: One ...

Goals - artificial intelligence: One desirable way to make perfect an agent's performance is to enable it to have some details of what it is trying to complete. If it is given

Hard and soft real time systems, Q. Hard and Soft Real Time Systems? ...

Q. Hard and Soft Real Time Systems? Hard Real Time Systems that guarantee critical tasks are completed on time. Soft Real Time Systems that are less restrictive type o

State about an active graphics device, State about An active graphics devic...

State about An active graphics device An active graphics device allows the user to communicate with the computer graphically. Generally, this implies that the user is supplyin

Padovan string, how to write this program,what are the declaration and func...

how to write this program,what are the declaration and function are needed in java program in java // aakash , suraj , prem sasi kumar kamaraj college program 1 : pack

Final year project, i want to make final year project in wireless.please he...

i want to make final year project in wireless.please help me to decide the topic???????

Calculate width and height of the grid, Given a cell, we must determine its...

Given a cell, we must determine its neighbouring cells i.e. those with which it shares a wall. The cells with an x are the neighbours of the cell c. Write the function getneighbour

Name a different return types of a controller action method, The following...

The following are just a few return types of a controller action process. In common an action process can return an instance of an any class that derives from Action Result class.

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