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FOLDED A folding editor (c) 1989 By Todd Burkey 1.0 GENERAL: FOLDED is a dual mode editor that provides several advanced features not currently found in text and programming editors. FOLDED is primarily intended to be used as a source code editor. As such, it incorporates a folding feature similar to that found in thought processor programs but with added support for the C language (and eventually Pascal). FOLDED also has some relational capabilities. These allow the user to associate lines in their source files with sections of their documentation files and vice-versa. And both folding and relations are incorporated in such a fashion that they don't impact the original text files in any way. 2.0 FEATURES: FOLDED also has the standard set of editor features, with a few bells and whistles thrown in. It has dynamic 'as-you-type' searching, substitution by block/global/direction of a string or exact word match (i.e. change variable i to i_var throughout your code), block copy/move/kill in normal or rectangular region modes, marks that allow intra-buffer movement, easy movement between buffers, a trash can, variable skipping (point to a variable, press ^n to skip to the next occurrence of it, ^p for previous), configuration save (you can leave a multi-buffer edit session and come back to the exact place you left off with all buffer positions restored), built in help, prompting for the beginning user, one-key buffer cloning, and more. 3.0 LIMITATIONS: So what doesn't FOLDED do? Well, the first release will not have an UNDO feature. The trash can will have to do. It also is dual mode, something which may alienate some of the Emacs users out there (I am bi-editable, since I use Emacs on some systems, graphic shell editors on others, vi on still others). With a little work, the editor could actually be made to work either as a dual mode editor or a single mode editor (hint to hackers out there). It also could use some better screen optimization, since I tended to develop it on high speed displays. It is usable at 2400 baud, but any slower than that and you are better off with ed. The first release also won't have any key binding capability. I still haven't decided upon the best approach to handle user-defined key maps. Finally, FOLDED isn't a layered editor. My goals during the development of FOLDED were to keep it relatively small (it is about 70K executable, <6000 lines of source) and fast, so layering as implemented in emacs-like editors was out. 4.0 HISTORY: I wrote FOLDED simply to learn. Early on, I made a choice to 1) put basic 'must-have' functionality in the editor, 2) put advanced concepts into the editor that can't be handled by external programs (folding and relational features), 3) implement a simple to use and understand multi file editing capability so that moving between files and scratchpads was easy, 4) design the editor so that I could add enhanced 'wish-list' functionality as I determined I needed it, 5) ensure that the final version of the editor would function the same on my Atari ST at home as it does on the Sun or Apollo workstations and even as it does on the mainframes, and 6) keep the program small (I hate long loading times). The latter requirement somewhat dictates the earlier ones...at least for the first release. Having used many editors over the last 15 years, I decided to implement (or try to anyway) the features I liked most in the various editors. This decision steered me away from any thoughts of modifying an existing editor like emacs or vi, hence I diverged from the 'standard' a bit. First, FOLDED is an unconstrained editor. You can move your cursor anywhere on the screen and when you enter insert mode (or copy a rectangular block of text) FOLDED will take care of sticking in needed spaces. Another difference is that the editor does not 'wrap' lines. Instead, you can scroll/page the entire window sideways when necessary (the editor will do this for you if you are typing past the end of the right margin). I got too used to this feature on the Apollos, I guess. Also, FOLDED does not retain tab characters. Rather, they are replaced with white space on input and FOLDED will optionally 'optimize' your file when you write it out (i.e. inserting tabs wherever it can, removing trailing spaces on lines, etc). Actually, FOLDED doesn't even retain leading spaces in the way you might expect an editor to store them. All leading spaces in a line are compressed to an integer variable upon file read-in. The user still sees the spaces on the screen, but internally this sped up my folding logic (at the cost of almost going insane over the added code complexity... there is always a tradeoff). 5.0 COMPATIBILITY: The first release of FOLDED has been tested on BSD4.2/3 (Suns, Symetric, and Apollo), SYSVR3 (ETA-10...haha), the IBM PC, and the ATARI ST. It is being ported by others to the Mac. A preliminary port of the code to the BELLCORE MGR (window manager) environment took only two hours on a Sun workstation and provided individual windows for each buffer (with title bars). 6.0 EDITING COMMANDS: When you invoke FOLDED the first time, press the ? key to see a cheat sheet that tells you what each key does. The following section covers the FOLDED commands in more detail. Note that whenever you are prompted for something in FOLDED, you will see the default response inside of brackets. Pressing the Return key will select this response. Also, in most cases, pressing the ESC key will return you to the top level command mode of FOLDED. It is important to remember that FOLDED is a DUAL mode editor. You start out in command mode and must use one of the insert commands to actually add text to the file you are editing. While in insert mode, you will continually be informed of this fact by a status line on the bottom of the screen. 6.1 REPETITION: Sometimes, you will wish to execute a command more than once. To do so, press the number keys to indicate the number of times you wish to do something and then do it. For example, if you wish to move down 4 pages, press 4J or if you wish to delete 8 characters, press 8d. Currently, only the movement and character delete commands utilize the feature. 6.2 MOVEMENT: The standard 'rogue' keys are used for single character cursor movement :-). Thus, the 'k' key will move you up one character, the 'j' key will move you down one character, the 'h' key moves you left one character, and the 'l' key moves you right one character. As a natural extension of this, I chose to have the 'K', 'J', 'H', and 'L' keys move you farther in the same directions. For example, 'K' and 'J' will page you up and down, while the 'H' and 'L' keys will move you 20 characters to the left or right. If you are using an ATARI ST, then the arrow keys also function for cursor movement. You can also go to the beginning of a line by pressing the '^' key and go to the end of a line by pressing the '$' key. To go to a specific line number, just press the 'g' key and you will be prompted for the line number you wish to go to. For those of you who prefer the jump-page technique over scrolling, you can toggle between the two modes by pressing the 'p' key. 6.3 READING: FOLDED allows you to read files in a variety of ways. The standard way is to simply invoke FOLDED with a list of files to edit. When you are in FOLDED, you can read a file into a new buffer by using the ':r' keys. If you wish to view a file (i.e. not be able to edit it), then use the ':v' keys. And, if you wish to insert a file into the current buffer, then use the ':i' keys. In each case, you will be prompted for the file name you wish to read in. Another way of reading files is to simply position the cursor over a file name and press '^r' (Control-r). Likewise, you can press '^v' if you just want to view the file. Another way files are read in by FOLDED is 'on-demand'. This method is used by the relation commands to pull a file in if you request FOLDED to go to a related line and the necessary file isn't already read in. It is also used by the '-c' option when you invoke FOLDED to read all the files back in that you were editing when you last 'saved' a session. In both cases, FOLDED will place you at the correct position in the buffer. 6.4 WRITING: Writing files in FOLDED is a bit less complicated. To write out the current buffer, press the ':w' keys. If you happen to be in a 'blok'ed off region, you will be asked if you just want to save that region to a file. Then you are prompted for a file name. After entering the file name, you can optionally be prompted as to whether you wish to optimize the output text or not. If you choose to optimize, then tabs are inserted in the text wherever practical and tailing spaces on lines are stripped off. If not, then NO tabs will appear in the output text at all. Another way of saving files is to press the ':s' keys. This will 1) save a configurations file of which files you are currently editing (and where you are in each buffer), and 2) cycle through all edited files asking if you wish to save them. 6.5 INFO: A help cheat-sheet is available in FOLDED by pressing the '?' key from the top level command mode. If you aren't sure what is going on and '?' doesn't give you the help screen, then press the ESC key followed by the '?' key. If you want to know where you are in a file, or even which file you are currently editing, press the '=' key. You will see a highlighted line appear on the same line your cursor was on with the line and column number you are on relative to the file you are editing, the screen coordinates you are on, and the file name. Pressing the '=' key again will revert your line back to normal. One final type of information is available by pressing the 'X' key. This will display a full screen of info showing all the files you are currently editing, the number of lines, where you are in the file, part of the text in the line you are 'on' in the file, etc. 6.6 SEARCHES: Searching is an important part of using an editor from a programmers' viewpoint. It needs to be fast and consequentially involve as little typing as possible. To this end, I implemented two distinct types of searching in FOLDED. These are dynamic searching and word searching. Dynamic searching is similar to that used in many of the micro-emacs implementations. By pressing the '/' key in FOLDED, you will be prompted for what you wish to search for. As you type, FOLDED will search for what you are typing, moving you visibly to the line you are searching for and warning you when you have typed something that doesn't match. As you are searching in this fashion, the Backspace key will cycle you back to where the appropriate matches were found originally. Also the '^n' and '^p' keys will find the next or previous occurrences of the string you last found. The ESC key must be used to exit this mode of searching. Note that using the '/' key provides forward search capability and the '\' key provides backwards search capability. Also, when you press the '/' or '\' keys, you will see the last thing you searched for inside brackets. Pressing the return key when you see this will continue your search for the same text. This becomes very handy when you are searching multiple buffers for a string. Word searching is even easier. You just position you cursor over a word and press '^n' or '^p' to find the next or previous occurrence of the word. By default, the search is inclusive, so FOLDED will look for the next string that contains the word. If you press the '^e' key sequence before doing your searches, EXACTMODE searching will be enabled. This simply means that only exact word matches will be used during word searches. This turns out to be handy if you are checking to see where variable 'i' is used throughout a procedure. Pressing '^e' a second time turns off exact mode (it is a toggle). Note: Searching in FOLDED currently doesn't support any regular expression parsing. I thought I would miss this, since I find it mandatory in VI and EMACS, but so far I haven't needed it enough to bother sticking the code in (I did work out some of the logic to do the most common VI/EMACS REGEXP options). 6.7 BUFFERS: A number of commands allow movement between buffers. Direct selection of a new buffer is made using: 1) the space bar to cycle through the buffers one at a time, 2) the '^g' key sequence to allow you to go to a buffer directly (more on this later), 3) the 't' key to toggle back and forth between two buffers, and 4) the 'T' key to toggle back and forth between a buffer and the trash can. Whenever you go to a buffer using these methods, the screen will be repainted with the contents of the destination buffer and the name of the buffer will be displayed at the bottom of the screen. Using '^g' will allow you to cycle through the list of buffers at the bottom of the screen using the 'j' and 'k' keys to scroll and the Return key to select. If you forget how to do this, press the '?' key after pressing '^g' and you will get some help. Indirect selection of a buffer is made when you 'goto' a relation and FOLDED automatically moves you to a new buffer, or as mentioned earlier, when you read in a new file. Another way you can end up in a new buffer is by pressing the 'c' key. This will create an empty (scratch) buffer and place you in it. Pressing the 'C' key will make a complete copy (clone) of your current buffer into a new one and place you in it. Finally, using the '-k' key sequence will allow you to kill your current buffer (you will be prompted for verification before FOLDED does so), and then you will be moved to a previous buffer. Note that 'killing' the Trash Can simply empties it and leaves you sitting in the Trash Can buffer. Several comments are appropriate here about the Trash Can buffer. Every line you delete or multiple character sequence you delete will be moved to this buffer. Obviously, when you delete things from the trash can, they are really, truly gone. The Trash Can can be used as a scratch pad. In fact, the 'y' key will automatically insert the last line your cursor was positioned on in the trash can directly into your current line in another buffer. This is kind of like having an editable cut and paste buffer. Note that the Trash Can isn't automatically saved out by FOLDED, but it can be written out using ':w'. 6.8 BLOCKS: You can do things with regions of text in FOLDED using the 'blok' option key ('b'). Selecting this key will present you with the following prompt: blok-? (Start, End, Box, Norm, Move, Copy, Kill, Unset, Fold, Line <ESC>) Where the options are defined as follows: -Start = current cursor position defines start of block -End = current cursor position defines end of block -Box = rectangular cut and paste region -Normal = normal cut/paste region -Move = move block in buffer somewhere else -Copy = copy block in buffer somewhere else -Kill = move block to the trash can -Unset = undefines a block -Fold = fold a block -Line = block the current line -ESC = The escape key aborts the blok option command If you select the Move or Copy operations, FOLDED will further prompt you about where you wish to move the current buffers block to. The prompt you will see will be: To which buffer (c-current, t-tagged, s-select one) [ESC] ? Again, the ESC key will abort the blok option command. The 'c' key will simply copy the block into the same buffer at the cursor position. The 't' key will copy the block into the buffer most recently tagged with the '^b' key (tag buffer key). Finally, the 's' key will put you into the same type of selector window that the '^g' key uses to select a buffer to go to. In all of these cases, when you are pushing a block of text to another buffer, the block will be inserted in the destination buffer immediately following the line that you were last on in that buffer (or in the line after the cursor if you are doing a box region copy/move). This method was implemented to ease the 'building' of code fragments from a number of other buffers (i.e. you are editing a file and realize you need a small code fragment from another file, so you press '^b' to mark you current buffer as the tagged buffer for copies, press ':r' and enter the other file name, find the text you want using the '/' key, use the 'bs' and 'be' keys to define the start and end of the block, press the 'bct' keys to do a block copy to the tagged buffer, and then press the 't' key to move back to where you were before you started.) 6.9 CHANGING: Two mechanisms exist for changing (substituting) text using FOLDED. First, the 's' key can be used to simply replace a single character. Just move the cursor over the character you wish to change, press the 's' key, FOLDED will prompt you for the new character, press it, and you are done. If you want to perform string or word substitutions, press the 'S' key. FOLDED will prompt you for the text string you wish to search for (the word under the cursor is your default response), and then prompt you with what you wish the word to be changed to. Then FOLDED prompts you for the nature of the search and replace logic to use. Your choices are: Option (A-all, U-up, D-down, E-exact, <ESC>) [once]: If you select 'A', then all occurrences of the string are searched for and the substitution is made. If you press 'U' then replacements are made from the current position and on up in the buffer. If you press 'D', then the replacements work downward in the buffer. If you press the 'E' key, the replacements are by exact word match only. Finally, if you just press the return key, then only the first match is changed (i.e. this is a quick 'change word' command). Note that if you define a 'blok'ed region of text and happen to have your cursor inside that region when you do a substitution, you will be prompted as to whether you want your substitutions restricted just to that region of text. Also, keep in mind that folded away text is NOT affected by a global substitute. If you need to do a global substitute that looks inside folds, press the '^f' (unfoldall) key first. 6.10 DELETING: To delete the character under the cursor, simply press the 'd' key. To delete the whole line you are on, press the 'D' key. If you wish to do global deletes of lines that contain or don't contain a particular string or word, press the '-d' or '-v' key sequences. The '-d' key sequence will delete every line that matches your search criteria, while the '-v' sequence deletes every line that does not contain it. Both sequences will prompt you for the string and ask if you wish the string to be inclusive or an exact word match. 6.11 INSERTS: Inserting text into a buffer is quite simple. Simply move your cursor to where you wish to start inserting and press the 'i' key to start inserting before the cursor. When you are done typing in text and wish to move to another part of the file or use any of the editor commands, just press the ESC key. Note that while you are insert mode, you will see the following prompt in bold at the bottom of the screen: Insert mode (^p-toggle auto indent). <ESC> when done. so it is pretty hard to forget how to get out of insert mode. The '^p' key sequence may be used to turn off the auto-indent mode. Currently, auto-indent is always turned on by default (this will be handled via a configuration file in future versions. Three other commands are available for inserting text. The 'a' key is just like the 'i' key, except it starts inserting text after the current character under the cursor. The 'I' key will insert a line in front of the current line, tab over so that the new line is indented to the same level as the previous line, and then puts you into insert mode at that positions. The 'A' key does the same thing, but creates the line after the line that your cursor is on. 6.12 FOLDING: Folding is a complex enough topic that it is further described in Appendix 1. The following is simply a list of the current set of commands that involve folding: f-fold by indentation, F-fold by logic, bf-fold a defined block ^f-toggle unfoldall, NOTE: press f or F on a fold to unfold it 6.13 RELATES: Relations are also a complex topic. For further information, see Appendix 2. The current set of commands are defined as follows: Rsl-Relate Set Line Rsw-Relate Set Word Rgl-Relate Goto Line Rgw-Relate Goto Word Rkl-Relate Kill Line Rkw-Relate Kill Word Rp-Relate Pop 6.14 MARKING: Marks are a handy feature to get used to, since they let you move around within and between buffers in a very efficient manner. FOLDED utilizes a one character global mark concept. All mark commands are invoked by first pressing the 'm' key. The user then sees the following prompt: mark-? (Set, Goto, Kill, Clear all, <ESC>) Answering 's' will prompt the user for a keypress and assign the current location (line number, character position, buffer number, etc) to that key. For example, typing 'msa' will assign the current location to the 'a' key. Answering 'g' will prompt the user for which tag to go to. For example, to get to the location tagged with the 'a' key, you simply type 'mga' and you will be immediately moved to that location. Note that FOLDED searches in the current buffer for the 'tag key' first and then scans all buffers. If you answer the prompt with a 'k' FOLDED asks whether you wish to kill the tag(s) associated with the current line or a specific key (you either press the key or press return to select the current line). So pressing 'mka' will remove the tag associated with the 'a' key. Finally, select the 'c' option if you wish to remove all tags defined in the current buffer. 6.15 EXTRAS: One of the most important commands you will need to remember is the 'Q' key. Pressing this key will exit you from FOLDED. If you have any buffers that have been modified, but haven't been written to a file yet, FOLDED will ask you if you are sure you wish to exit. Note that on most systems, pressing CTRL-C will accomplish the same effect as pressing 'Q', although the effect will be immediate if the compiler/OS used doesn't support signals (CTRL-C is normally trapped to vector you to the same routine that pressing 'Q' does). Also, on BSD systems, pressing CTRL-Z will cleanly interrupt your editing session and allow you to resume at a later time (via fg). If you wish to invoke a shell or run an external program from within FOLDED, simply press the '!' key and either press return when prompted, to start up a shell, or type in the command you wish to run. To execute an external macro on the currently 'blok'ed region of text, press the 'x' key. Right now, this command is experimental and really should be considered unimplemented. I am still toying with different ideas in the definition and implementation of external macros. Note that having external macros does not preclude having internal macros at some future date. 6.16 KEY TRAINING: Occasionally, you will realize that you have to do something really fairly simple a number of times. The use of the 'trained key' concept in FOLDED comes in useful here. To turn on key training, press the '[' key. You will be informed that key training is now turned on and that you can turn it off with the ']' key. Now do whatever sequence of commands you need to do and press the ']' key. You will be informed that the 'e' key has now been trained. Now, every time you press the 'e' key you will see the exact same sequence of commands performed. Note: the training does not carry over between edit sessions, but it will carry over as you switch between buffers (in fact, switching between buffers may be part of what the key is supposed to do). Also keep in mind that this can be a fairly dangerous command, so keep the complexity of what your are trying to do down until you are comfortable with the feature. 7.0 BACKUP PROTECTION: If FOLDED detects a local directory called febackup, then backup copies of anything you edit will be placed in that directory. A rename operation is performed on the original file, so this means that only local partition files will be backed up in this fashion. Backups only take place at the time you save a file the first time during an edit session, so no unnecessary backups are made. 8.0 FOLDED CONTROL FILES: If folded detects a local directory called foldinfo, then FOLDED will store all its control files there rather than clutter your directory with them. A control file is created only when the file being edited is saved and has some folding or relations in it. The control file will be a file of the same name, but with an 'f' inserted immediately after the final '.' in the name...so 'test.c' has a control file called 'test.fc' and 'junk' would have 'junk.f'. 9.0 ENVIRONMENT VARIABLES: Several Environment variables may be used if you wish to avoid some prompting by FOLDED. They are: FE_ASCII - Save control files in ASCII (easier to mail that way) FE_BINARY - Save control files in BINARY (a bit faster and more efficient). FE_NOTABS - Always write files without tabs (useful on the Apollos). FE_TABS - Always fully optimize the files when writing. MGR_FONT - Size of the font used under MGR for the windows. 10.0 Coding Style I expect to take some flak on my coding style. I wrote most of this editor in evenings after LONG days of mostly Pascal code design at ETA, so I tended to keep things fairly simple, brute forcing the code where necessary. Most of the current code I wrote as throwaway test code and just haven't had time to re-design the logic. I also didn't originally plan on releasing the sources to this code, so it is set up in such a manner that I can go back to it a year or two from now and immediately be able to pick up where I left off. Unfortunately, this doesn't mean there is sufficient in-line documentation for others to port by. After (if) I get gcc ported to my Symmetrics (or if I get a job working for a company that has a good ANSI compliant C compiler), I'll try to get FOLDED 'up to' ANSI C standards. I hopefully have put in sufficient IFDEF's to help minimize the porting issues, but feel free to send in any extra ones you find your type of system needs. 11.0 Obtaining Updates to FOLDED FOLDED is an evolving product. As such, I expect to make fairly frequent updates and release new versions several times a year (probably more often in the first year or so). If you have USENET access, then keep an eye on the sources newsgroups for diffs and/or new versions. If you want the next major release earlier than it trickles out to the net (i.e. a month or so earlier than normal), then follow the procedure outlined below but remember to specify which release you currently have. Of course, this would require that you have access to a PC or ST (or a floppy drive on your Unix system and the mdrive PD software). For those of you who received a binary only version of FOLDED (the PC or Atari ST versions), the most recent version with sources can be obtained by sending $20 to the address shown below. Please specify computer and media type. I can create SSDD or DSDD 3.5" disks for the Atari ST and 360K 5.25" disks or 720K 3.5" disks for the IBM PC. If you are outside the United States, then please add $5.00 shipping and handling (I prefer to ship by Air Mail). Ordering in this way will register you for a mailing notice of the next subsequent 'major' update. Todd Burkey 3546 Pilgrim Lane Plymouth, MN 55441 Home Phone (eve/wkends): (612) 542-1027 BBS I can be reached at: (612) 560-9254 Usenet Address via UUCP: pwcs!stag!trb 12.0 COPYRIGHT INFORMATION The following paragraph defines the basic copyright information for FOLDED. It is included at the top of each of the source modules and must NOT be changed or removed from this document without written permission of the author. This file is part of the FOLDED sources. FOLDED is a folding editor and is copyrighted 1989 by Todd Burkey, 3546 Pilgrim Lane, Plymouth, MN 55441. The author gives you the right to further distribute FOLDED, as long as 1) this notice remains intact in the sources, 2) the sources are made available to the end user, and 3) the editor isn't sold for a profit. The author makes no representations or warranties of fitness of this program for any purpose. As with any free program, you use it at your own risk. Appendix 1: FOLDING Obviously, a fundamental concept in using FOLDED is that of folding. Folding in a text editor is a mechanism that allows you to cause sections of code or text be replaced by a single line of text. This is useful for 'hiding' away clean and functional sections of code while you work on and only see the parts that you are currently debugging. It also proves useful for tucking away big comment blocks. Worried that folding will change your source code? Don't worry, the act of folding doesn't affect the edited file at all...even when saved. When you save a file that has folds in it, a separate control file is also saved under your current directory. See the section in the documentation titled 'CONTROL FILES' for more info on this. In FOLDED, I implemented three types of folding. In each case, a segment of your file is reduced such that all you see is the first line of the segment in reverse image (or bold, depending on your standout terminal mode). First, is the simple 'fold a marked block'. This allows you to mark any arbitrary region of text and fold it away. For example, lets say we had started with the following text (the numbers are just for reference in this documentation): 1: main() 2: /* GID for main - Just a test case 3: Author: Todd Burkey 4: Date: 1/27/89 5: DESC: Methodology for a test case 6: */ 7: { 8: if(this==that) { 9: do_something_that_works(); 10: } 11: } By defining a region between lines 2 and 6 and then folding, what you would see on the screen would be: 1: main() 2: /* GID for main - Just a test case <-pretend this line is bold 7: { 8: if(this==that) { 9: do_something_that_works(); 10: } 11: } Another method of folding is that based on 'indent level'. The logic behind indent level folding is simply to start with the line the user is currently on, move down in the text until an indent occurs, and then continue down until an undent occurs that is less than or equal to the original lines 'indented' position. For example, if you had been on line 8 in the above 'folded' text when the 'f' key was pressed, you would see the following: 1: main() 2: /* GID for main - Just a test case <-pretend this line is bold 7: { 8: if(this==that) { <-pretend this line is bold 11: } Unfortunately, most source code contains lots of things that tend to break up the clean indentation levels, so I added a third folding mechanism. This one is a little smarter in that it does a 'logical fold'. A logical fold looks for logical block begin/end marks in the code (the braces in C) and skips around comments, strings, etc. For example, if you had pressed the 'F' key on line 1 in any of the above steps, you would end up with: 1: main() <-pretend this line is bold In all cases, unfolding the text is performed by simply moving to the folded line and pressing the 'f' or 'F' key. Folding isn't all that novel a concept. It has been used for years now in thought processor programs on the Mac, IBM PC, and even back in the CP/M days. Thought processors usually use the 'fold by indent level' technique. Take the following simple example: FOLDED Information * specifications <-pretend this line is bold * plans <-pretend this line is bold * problems <-pretend this line is bold This is all I see when I use FOLDED to call up my folded.info file. Now, if I move to line 3 and press the f key, I will see: FOLDED Information * specifications <-pretend this line is bold * plans - Documentation <-pretend this line is bold - Enhancements <-pretend this line is bold - Bullet-proofing <-pretend this line is bold * problems <-pretend this line is bold In summary, folding is fully hierarchical (i.e. a fold can contain any number of folds), it is smart (it can fold based on programming logic blocks and indentation level), and it is retained from one edit session to the next. The actual commands (and their associated key bindings) that involve folding are: indent fold (f) : fold based on indent level logic smart fold (F) : fold based on {} logic unfold (f or F) : unfold the fold under the cursor temp unfold (^f): temporarily unfold all folds (for searching/sub'ing) re-fold all (^f): yep, CTRL-f is just a toggle block fold (bf): fold current block region Appendix 2: RELATING The word 'relations' in the field of databases conjures up images of opening up a large database, finding a particular entry, moving to a particular field, and, with several keystrokes, calling up not only another database, but a specific record in that database. Now, I have never understood why we couldn't have similar capabilities in a text editor. We can envision having a document file, moving to a specific part of the document, calling up the source code file related to that part of the document, and then moving to the appropriate spot in the source file. We can even imagine moving through the source code and finding a structure (or variable) and wishing we could immediately view the definition of the structure. These scenarios are fundamentally the same as those handled by a relational database program. Relationships as pertains to editors (and, of course, in this context, FOLDED) primarily involve two concepts. First, there are word relationships. These are something like 'glossary' entries in that you define a word once in a file and then can immediately go to the exact place you defined it from anywhere in the file (or any other file you are currently editing.) From a programming viewpoint, this simply means that you can move your cursor over a structure name in a source file and with a few keystrokes be placed immediately in an include file at the place the structure is defined. A second relationship type is that of line relations. These are basically invisible links that relate a line in one buffer to a line in another buffer. This type of relationship allows you to easily move back and forth between source code and program outlines/documents. Folded will even open up a file if you try to go to a relation in a file that you aren't currently editing. FOLDED supports a number of commands that allow easy creation and use of these relationships. The following key sequences are used to perform the most common relation operations: Rsl (Relate Set Line): The current line becomes 1/2 of a line relationship. The next Rs command will complete the relationship. Rsw (Relate Set Word): The current word is indexed for reference. Rgl (Relate Goto Line):FOLDED looks at the first line with a relation on or above the current line and goes to its related line. If the related line is in a file not currently being edited it will be opened for viewing. Rgw (Relate Goto Word):Read the word under the cursor and move to the correct file that it was defined in. Rkl (Relate Kill Line):Kill the relationship for the current line. Rkw (Relate Kill Word):Kill the relationship for the current word. Rp (Relate Pop): Pop back to where you were before the last Relate Goto. The pop stack is currently 10 levels deep. As with folding, the relationship information does not affect the actual files you are editing. In fact, the information is simply saved out as part of the folding info files. It is also important to note that neither folding or relations affect the speed of loading, saving, or using the various editor features to a notable extent. Since I added relations very late in the development of the editor, I have a feeling that this area will see the most improvement over the next year. I've already decided that I need a few more commands to do things like 'move' and 'view' relationships. Appendix 3: IMPLEMENTATION DETAILS Folded uses a doubly linked list to store lines internally. It mallocs the exact amount of memory a line needs on read-in, but as you modify lines it will malloc additional memory in 4 byte chunks...so you can end up with some wastage if you edit a lot of lines in a file. FOLDED keeps track of a lot of information about lines in the buffers, so there is quite a bit of overhead in using FOLDED. I place it pretty close to emacs in the amount of overhead required for 'data' storage, but since the executable is only about 60K it wipes emacs away in raw loading time (program+files). I haven't had time to optimize the code for speed yet, but things like searching and substituting are significantly faster than emacs and slightly faster than vi. This is partly due to the design of the editor and also may be due to FOLDED's lack of regular expression parsing routines. The first version of FOLDED isn't as optimized as it could be in the sense that ints may be used where chars may get by. Also, there may be tricks I don't know about that could compress the amount of overhead I incur in the storage of lines, buffers, etc.