DIBOL for Beginners

This document, "DIBOL for Beginners" (Order No. AA-BI77A-TK, April 1984), serves as an introductory manual to the DIBOL (Digital's Business Oriented Language) programming language. It is specifically designed for professionals with no prior programming experience.

The manual aims to teach the fundamentals of programming, as well as the vocabulary and syntax of DIBOL, enabling readers to understand data processing concepts and write simple DIBOL-83 programs. It covers:

• Introduction to Computers: Explains hardware, software, and how data is stored in a hierarchy (data base, file, record, field, character) and accessed (sequentially or directly).
• Data Processing Fundamentals: Describes the basic input-processing-output cycle, the concept of loops, and the use of flowcharts with standard symbols to visualize program logic.
• Steps for Writing DIBOL Programs: Outlines a nine-step process: defining the problem, flowcharting the solution, coding, keying in, compiling, linking, running, debugging, and documenting the program.
• DIBOL Language Syntax: Details the program structure (Data Division, Procedure Division, PROC, END statements), types of DIBOL statements (Compiler Directives, Data Specification, Data Manipulation, Control, Intertask Communication, Input/Output), delimiters, and statement labels.
• Practical DIBOL Programming: Illustrates concepts with a sample "Customer Balance Program," explaining key statements like .TITLE, RECORD, OPEN, READS, IF, CALL, GOTO, WRITES, and CLOSE.
• Loops and Data Manipulation: Further explores loops using INCR and FOR statements, value assignment, and the rules for moving different types of data (alpha and decimal) between fields, including justification and truncation.
• DIBOL Math: Covers arithmetic operators, the order of operations (precedence), and how to change precedence using parentheses, noting DIBOL's integer-only math.

The manual is applicable to all products containing DIBOL-83 and runs on various Digital operating systems, including VAX/VMS, CTS-300, RSTS/E, Professional, RSX-11M-Plus, and Micro/RSX.