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

Convert the binary number to gray code, Convert the binary number 10110 to ...

Convert the binary number 10110 to Gray code ? Ans. For changing binary number 10110 in its equivalent Gray code the rules are as, the left most bit that is MSB in Gray code is 1

Isoquants, what are the types of isoquants

what are the types of isoquants

Explain the advantages of object oriented analysis design, Advantages of Ob...

Advantages of Object oriented analysis design The OO approach inherently makes every object a standalone component which can be reused within specific stat problem domains we

Describe type library and what is its purpose, Type libraries are files tha...

Type libraries are files that explicitly explain some or all of the contents of components. This haves information about the methods, properties, constants, and other members expos

Define e-commerce, Define e-commerce? The term 'electronic commerce' ha...

Define e-commerce? The term 'electronic commerce' has develop from electronic shopping, to imply all aspects of business and market processes enabled by the Internet and World

How transmission bridges help in satisfying the connectivity, How do tra...

How do transmission bridges help in satisfying the connectivity? A usual transmission bridge is demonstrated in figure. The series capacitance and the shunt inductances of

For what purpose Karnaugh map is used, Karnaugh map is used for the purpose...

Karnaugh map is used for the purpose of ? Ans. Karnaugh map is used for, to minimize the terms in a Boolean expression.

Subtraction of 01100-00011 using 2's complement method, Subtraction of 0110...

Subtraction of 01100-00011 using 2's complement method Ans. Firstly 1's complement of 00011 is 11100 and 2's complement is 11100 + 1 = 11101. Thus If a last carry is

What is the significance of nonactionattribute, In general, all public proc...

In general, all public processes of a controller class are treated as action processes. If you require prevent this default behaviour, just decorate the public process with NonActi

Assembly directives and pseudo-ops, Assembly directives and pseudo-ops: ...

Assembly directives and pseudo-ops: Assembly directives are which instructions that executed by the assembler at assembly time, not by the CPU at run time. They can build the

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