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

Detemine the major building blocks of uml, Detemine the major building bloc...

Detemine the major building blocks of UML UML could be used in visualizing, specifying, constructing and documenting object oriented systems. The major building blocks of UML a

Illustrate single in-line memory modules, Q. Illustrate Single In-line Memo...

Q. Illustrate Single In-line Memory Modules? From early days of semiconductor memory till the early 1990s memory was manufactured, brought and installed as a single chip. Chip

What is binary, Binary is an alternative number system which works very goo...

Binary is an alternative number system which works very good for computers. Humans have ten fingers; that's probably why we use ten digits (0, 1, 2, 3, 4, 5, 6, 7, 8, and 9) in our

By which except ions of type error in java are handled, Except ions of type...

Except ions of type error in JAVA are handled by? Except ions of type error in the JAVA are handled through JAVA run time environment.

Mathematical model, how to write mathematical model for circular linked lis...

how to write mathematical model for circular linked list

Task information displays in search-based tools, Q. Task Information Displa...

Q. Task Information Displays in Search-based tools? Task Information Displays principally give visualization of different locations in parallel program where bottlenecks have o

What are kinds of processors, Processors can broadly be seperated into the ...

Processors can broadly be seperated into the categories of: CISC, RISC, hybrid, and special purpose.

Explain the compiler - computer programming, Explain the Compiler - Compute...

Explain the Compiler - Computer Programming? The Compiler is a program that translates source code into object code. The compiler derives its name from the means it works looki

Computer architecture by henessy and patterson, what is initial interval an...

what is initial interval and latency in a functional unit(fp) of a pipeline

Show the dynamic range and colour depth, Q. Show the Dynamic Range and Colo...

Q. Show the Dynamic Range and Colour Depth? Dynamic Range is the number of colours a colour scan or number of grays a monochrome scanner can distinguish. The dynamic range is t

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