I had an interesting conversation at RPG World earlier this month. The discussion was about shop standards, which led to questions about the benefit of the use of "template programming." This technique is widely used in most AS/400 and iSeries shops. It involves the use of pre-written programs of various categories, such as work-with panels, subfield searches, and file maintenance.

Programmers copy these templates to create new applications, thus easily following the shop standards for screen layout and program structure. The other and perhaps more beneficial aspect of copying program templates is that programmers can get programs running more quickly if some of the code is already written for them.

I refer to program templates as "starter code," program source code that is used to get you started writing a program. A lot of commercial applications use starter code, including those that take advantage of wizards to generate customized starter code for an application. These wizards prompt the developer for a few variables and then copy the starter code--with a few modifications--to a destination library.

But what was interesting about this conversation is that it seems that no one updates their templates. They use program templates to help set shop standards, but they haven't updated those templates for (in some cases) years. One programmer admitted to using templates that had originally been created at least seven years ago.

While it is good to have shop standards--and it is a great idea to use program templates as starter code--it is my opinion that those templates should be reviewed annually. Programmers don't write applications the same way they did five years ago, so why should they have to use five-year-old templates to get them started?

Program templates that are not reviewed and updated periodically can contain code that is just as obsolete as those legacy applications we all love to hate. Here's a check list that you can use to verify whether or not a program template needs to be reviewed and brought into the 21^st century.

• Is it written in RPG III (aka RPG/400)? Then rewrite it.

• Is there an IFEQ, WHENxx, DOWxx, or DOUxx in the code? Then rewrite it, because it was simply ported from RPG III.
• Does it avoid RPG IV subprocedures? Then rewrite it.
• Does it take advantage of the INDDS? If not, review it to see if you can reduce the use of indicators throughout the code.
• Does it use function key response indicators to condition code? If so, review it and consider avoiding command key response indicators. Instead, use position 369 of the WSDS and named constants to respond to the function keys that are pressed.
• Does it use hard-coded literal values? If so, review it and move all the hard-coded values to named constants.
• Does it have standard values hard-coded in the Definition specifications? If so, review it and consider moving fixed values that are shared between all programs or all program templates into their own /COPY source member. Then, embed them back into the programs using a /COPY or /INCLUDE directive.
• Does it need to be compiled on multiple releases of OS/400? If so, review it and consider leveraging the conditional compiler directives. These are directives that allow you to include and omit source code based on the release of OS/400 that is being used to compile the program. The benefit here is that you can embed code that will do a particular task easily under a later release and retrofit it so it will work on older releases.

These are just a few of the things to take into consideration when reviewing or rewriting your shop's standard programming templates. If you don't have standard templates, you should consider creating some type of starter code library soon. It will help your developers leverage the skills of others. One thing to consider might be to have your best developer build the starter code/program templates and allow the others to review the code.

Bob Cozzi has been programming in RPG since 1978. Since then, he has written many articles and several books, including The Modern RPG Language --the most widely used RPG reference manual in the world. Bob is also a very popular speaker at industry events such as COMMON and RPG World and is the author of his own Web site, rpgiv.com.

Bob Cozzi is a programmer/consultant, writer/author, and software developer. His popular RPG xTools add-on subprocedure library for RPG IV is fast becoming a standard with RPG developers. His book The Modern RPG Language has been the most widely used RPG programming book for more than a decade. He, along with others, speaks at and produces the highly popular RPG World conference for RPG programmers.

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