Students' Guide to Program Design

Module design considerations

8.1 Module cohesion

A module has been defined as a section of an algorithm which is

dedicated to the performance of a single function. It contains a single

entry and a single exit and the name chosen for the module should

describe its function.

Beginner programmers often need guidance in determining what

makes a

good

module.

Common queries are 'How big should a module

be?',

Is this module too small?' or 'Should I put all the read statements

in one module?'

There is a method which programmers can use to remove some of

the guesswork when establishing modules. The programmer can look

at the

cohesion

of the module.