Subject: GFA Tutorial, The Editor By: James Collett (Professor) A Member Of: VIRTUAL INFINITY Email: s6005146@oxpoly.ac.uk (or s6005146@brookes.ac.uk) Address: Room N4, L.S.C.Collage, Wheatley, Oxford, OX9 1HX Mono accnt.: bcc Just before we delve in, a few shorts about the GFA Basic editor, which is different depending on whether you have version two or version three of the language. The editor is fairly straight-forward and is basically a specialised word processor or text editor for the language. When you first load the language you will find a blank screen (where you enter your source) and the menu at the top. If you are running version two then the menu should span from Load/Save to Run/Test. If you are running version three then this should be your basic menu with an Atari symbol on the far left and a clock of the far right. GFA 2 And GFA 3 Basic Menu ========================== Load & Save should speak for themselves, they load & save in GFA`s unique file structure or format, sometimes called a tokenised format. This is not only unique to GFA, but also unique to different versions of GFA. SaveA & Merge also load and save but in a standard ASCII format which can be loaded into a word processor, another version of GFA and even some other versions of Basic. You will Merge sources off this tutorial instead of loading for that very reason, so this tutorial can be compatible with various versions of GFA. Merge is also used to append or merge two sources together. When you Load the previous contents of the memory are wiped! If you wish to append two sources then Load or Merge the first, move the cursor to the correct position and Merge the second - just like a word processor. Llist prints the entire source currently in memory, assuming you have a printer connected and on line. The Block facility allows you to Copy, Move and Delete sections of the source; it also allows you to Write (SaveA) and Llist (print) sections of the program. Before you can use it you must mark out or high-light the block. Replace and Find allow you to either search for or search & replace a particular string (piece of text) in the source. Note that these are case-sensitive and in GFA 2 you can only search for entire lines, in GFA 3 you can search for sections of lines. The next pair of buttons are used for paging up and paging down; this is very labour-saving if you have more that a couple of screens full of text! Insert or Overwrite works just like and word processor, note that GFA defaults to Insert. The button above this is not spare, but only used when on monochrome (high res). Direct and Flip are both explained later this month. Finally Run is used to execute (interpret - discussed later) the source currently in memory. GFA 3 Extras ============ In GFA 3, as well as this basic menu, there is also a clock and line indicator to the far right. You can also use the line indicator to jump straight to a particular line of the source. To the far left, the Atari symbol displays a GEM menu which allows you to run resident accessories among other things. The small space under the Atari symbol indicates whether caps lock is on or not. Direct Mode And Editor Mode =========================== Anything you type on the editor screen will not instantly be run and will be added to the source. It is often useful to directly run something without interfering with the rest of the program - may be to test it before adding it to the source. This can be done by selecting Direct either from the menu or by hitting . GFA should now display an "OK >" prompt at which you can directly execute single lines (discussed this month). To return to the editor either type 'edit' or hit . GFA Editor Short-cuts ===================== On the editor mode, as well as clicking on the menu buttons at the top you can also use the function keys to select a bottom line button and plus a function key to select a top line button. Also in GFA 3, on the direct mode, you can use and to re-call lines you have already typed on the direct mode. ---END---