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

Building is into our operational processes, Building IS into our operationa...

Building IS into our operational processes - Information System Although information systems are becoming increasingly prevalent they are not always the correct solution to ev

Develop a calculator in masm, Assignment:  develop a calculator in MASM. ...

Assignment:  develop a calculator in MASM. Text chapters covered:  1 through 4, 5.4, 5.5, 6.3, 7.4 You will develop a "calculator" algorithm in MASM using reverse-polish nota

Asp.net, in asp project is i have to crate database every time when i move ...

in asp project is i have to crate database every time when i move my project on different server

External program components, How does the system handle roll areas for exte...

How does the system handle roll areas for external program components? Transactions run in their own roll areas. Reports run in their own roll areas. Dialog modules run

What are pages, What are pages? All programs and date are composed of f...

What are pages? All programs and date are composed of fixed length units known as pages. Each page consists of blocks of words that occupy contiguous locations in main memory

How is a multidimensional array defined pointer, How is a multidimensional ...

How is a multidimensional array defined in terms of a pointer to a collection of contiguous arrays of lower dimensionality ? C does not have true multidimensional arrays. Howev

Power supply in computer system, Q. Power supply in computer system? Co...

Q. Power supply in computer system? Computer operate electronically- either by power supply attained from your electric plug or batteries in case of portable computers. Though

How debugger works internally, Whenever we compile with -g option, it will ...

Whenever we compile with -g option, it will make a symbol table, and according that table for every function and line it will call ptrace.

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