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The Pseudo code

Programming Process

Code Complete

Author : Steven C. McConnell.

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Summary of Steps in Building Classes

and Routines

Creating a general

design for the class is an iterative process

class creation can be a

messy process for all the reasons that design is a messy process

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Steps in Creating a Class

Create a general design for the class

Construct each routine within the class

Review and test the class as a whole

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Steps in Building a Routine

creating a routine—designing the routine, checking the design, coding the routine,

and checking the code

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Pseudo code for Pros

“pseudocode” – English-like notation for

describing how an algorithm, a routine, a

class, or a program will work

Pseudocode Programming Process (PPP)

defines a specific approach to use

pseudocode to streamline the creation of

code within routines.

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Contd…

guidelines for using pseudocode

Use English-like statements that precisely describe specific operations.

Avoid syntactic elements from the target

programming language.

Write pseudocode at the level of intent.

Write pseudocode at a low enough level that

generating code from it will be nearly automatic.

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Contd…

Example of Bad Pseudocode increment resource number by 1

allocate a dlg struct using malloc

if malloc() returns NULL then return 1

invoke OSrsrc_init to initialize a resource for the operating system

*hRsrcPtr = resource number

return 0

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Contd…

Example of Good Pseudocode Keep track of current number of resources in use If another resource is available Allocate a dialog box structure If a dialog box structure could be allocated Note that one more resource is in use Initialize the resource Store the resource number at the location provided by the caller Endif Endif

Return TRUE if a new resource was created; else return FALSE

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Constructing Routines Using the PPP

the activities involved in constructing a

routine

1. Design the routine

2. Code the routine

3. Check the code

4. Clean up leftovers

5. Repeat as needed

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1. Design the Routine

Check the prerequisites

Define the problem the routine will solve

Name the routine

Decide how to test the routine

Think about error handling

Think about efficiency

Research functionality available in the standard libraries

Research the algorithms and data types

Write the pseudocode

Think about the data

Check the pseudocode

Try a few ideas in pseudocode, and keep the best (iterate)

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2. Code the Routine

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3. Check the Code

Mentally check the routine for errors

Compile the routine

Step through the code in the debugger

Test the code

Remove errors from the routine

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4. Clean Up Leftovers

take several cleanup steps to make sure that the

routine’s quality is up to your standards

Check the routine’s interface

Check for general design quality

Check the routine’s data

Check the routine’s statements and logic

Check the routine’s layout Check the routine’s documentation. Remove redundant comments

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5. Repeat Steps as Needed

If the quality of the routine is poor, back up to the pseudocode. High-quality programming is an iterative process, so don’t hesitate to loop through the construction activities again.