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A Generalized Approach Using Outlines and Pseudo Code






Software virtually never springs to life in any sort of initially finalized form. It typically evolves through multiple revisions, and often develops in directions originally unanticipated. There's no perfect process to achieve final designs from scratch, but certain approaches typically do prove helpful. Having a plan of attack is what gets you started writing line 1 of your code, and it's what eventually delivers a working piece of software to your user's devices. Here's a generalized routine to consider:

  1. Start with a detailed definition of what the application should do, in human terms. You won't get anywhere in the design process until you can describe some form of imagined final program. Write down your explanation and flesh out the details of the imaginary program as much as possible. Include as much detail as possible: how will the user interact with it, what sort of data will it take in, process, and return, etc.
  2. Determine a list of general code and data structures related to each of the 'human-described' program goals above. Take stock of any general code patterns which relate to the operation of each imagined program component. Think about how the user will get data into and out of the program. Will the user work with a selection lists, text input fields, etc? Consider how the data used in the program can be represented in code, organized, and manipulated. What types of data will be involved (text types such as strings, time values, or URLs, binary types such as images and sounds, etc.). Could the program code potentially make use of variables, list structures and functions, etc? Will the data be stored in local files, in remote files, in a database, or just in temporary memory (variables), etc? Think of how the program will flow from one operation to another. How will pieces of data need to be sorted, grouped and related to one another, what types of conditional and looping operations need to be performed, what types of repeated functions need to be isolated and codified into functions, subroutines, etc? Consider everything which is intended to happen in the imagined piece of software, and start thinking, " _this_ is how I could potentially accomplish _that_, in code...".
  3. Begin writing a code outline. It's often easiest to do this by outlining user interactions, but a flow chart of operations can be helpful too. The idea here is to begin writing a generalized code container for your working program. At this point, the outline can be filled with simple natural language PSEUDO CODE that describes how actual code can be organized. Starting with a user interaction outline is especially helpful because it provides a starting point to actually write large code structures, and it forces you to deal with how the program will handle the input, manipulation, and output of data. Simple structures such as " menu option (which does this when clicked...)", " list: (with labels and sub-lists organized like this...), " function: (which loops through this block and saves these elements to another variable...)" can be fleshed out later with complete code.
  4. Finally, move on to replacing pseudo code with actual working code. This isn't nearly as hard once you've completed the previous steps. The API reference is very helpful at this stage. And once you're really familiar with all the available constructs in the language, all you'll likely need is an occasional syntax reminder from RFO Basic's help documents. Eventually, you'll pass through the other design stages much more intuitively, and get to/through this stage very quickly.
  5. As a last step, debug your working code and add/change functionality as you test and use the program.

The basic plan of attack is to always explain to yourself what the intended program should do, in human terms, and then think through how all required code structures must be organized to accomplish that goal. As an imagined program takes shape, organize your work flow using a top down approach: imagined concept -> general outline -> pseudo code description / thought process -> working code -> finished code.

The majority of code you write will flow from one user input, data definition or internal function to the next. Begin mapping out all the things that need to " happen" in the program, and the info that needs to be manipulated along the way, in order for those things to happen, from beginning to end. The process of writing an outline can be helped by thinking of how the program must begin, and what must be done before the user starts to interact with the application. Think of any data or actions that need to be defined before the program starts. Then think of what must happen to accommodate each possible interaction the user might choose. In some cases, for example, all possible actions may occur as a result of the user selecting from a list of menu options. That should elicit the thought of certain bits of select function structure, and you can begin to write the code outline to implement those choices.

Whatever your conceived interface, think of all the choices the user can make at any given time, and provide a user interface component to allow for those choices. Then think of all the operations the computer must perform to react to each user choice, and describe what must happen in the code.

As you tackle each line of code, use natural language pseudo code to organize your thoughts. For example, if you imagine a menu choice doing something for your user, you don't need to immediately write the RFO Basic code that the menu choice runs. Initially, just write a description of what you want the choice to do. The same is true for functions and other chunks of code. As you flesh out your outline, describe the language elements and coding thought you conceive to perform various actions or to represent various data structures. The point of writing pseudo code is to keep clearly focused on the overall design of the program, at every stage of the development process. Doing that helps you to avoid getting lost in the nitty gritty syntax details of actual code. It's easy to lose sight of the big picture whenever you get involved in writing each line of code.

As you convert your pseudo code thoughts to language syntax, remember that most actions in a program occur as a result of conditional evaluations (if this happens, do this...), loops, or linear flow from one action to the next. If you're going to perform certain actions multiple times or cycle through lists of data, you'll likely need to run through some loops. If you need to work with changeable data, you'll need to define some variable labels, and you'll probably need to pass them to functions to process the data. Think in those general terms first. Create a list of data and functions that are required, and put them into an order that makes the program structure build and flow from one definition, condition, loop, menu selection, action, etc., to the next.


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