POSITION-ORIENTED PROGRAM SPECIFICATIONS

To simplify writing RPG programs, various preprinted specification forms are available. These forms allow an application program to be written while making certain the correct positions are used. The source statements that make up an application program are transferred to the computer for compilation. This process, known as desk coding, was very popular before the onslaught of desktop personal computers, with their full-screen editors, as well as the full-screen editor available with the OS/400 operating system.

Very little desk coding is done any longer. Programmers usually write pseudocode (a free-format, English-like, logic-based language that is not compiled). The pseudocode is translated, by hand, into a high-level language. Pseudocode strongly resembles PL/I. When translating pseudocode into a high-level language, such as RPG, a full-screen editor or integrated development environment (IDE) is used to provide a more productive environment with fewer typing errors. This can result in fewer errors being placed into the source program.

Several full-screen editors are available to the RPG programmer, including CodeStudio, a GUI Microsoft Windows-based IDE for RPG and DDS; SEU, the source editor that comes with OS/400; and the GUI-based IDE offered by IBM. These source-code editors provide prompts that allow RPG program statements to be written easily. The editors correctly format the program statement to match the RPG specification.

A programmer with experience writing RPG programs using 80-position cards on an IBM 029 or 129 keypunch machine will appreciate using an online, full-screen editor or IDE that checks the syntax of statements as they are entered. A novice programmer typically makes a few mistakes anyway and will benefit from the assistance of these RPG editors offer.