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Text File | 1994-02-13 | 28KB | 678 lines

Every Emacs and Emacs varient I've ever used has had some variation of this file. AME is no different. For its TUTORIAL, I've found the GNU tutorial and modified it to match AME and the Amiga. After all, Emacs just isn't Emacs without a tutorial. - andy finkel --------------- Copyright (c) 1985 Free Software Foundation, Inc; See end for conditions. You are looking at the AME tutorial. AME commands generally involve the CONTROL key (labelled CTRL) or the META key (labelled ESC). Rather than write out META or CONTROL each time we want you to prefix a character, we'll use the following abbreviations: C-<chr> means hold the CONTROL key while typing the character <chr> Thus, C-f would be: hold the CONTROL key and type f. M-<chr> means type <ESC>, release it, then type the character <chr>. "<ESC>" stands for the key labelled "ESC". The M stands for Meta. Important note: to end the AME session, type C-c. (One character.) Other important note: In the various AME displays, a control character will be displayed with a leading caret, ie ^C is control C. The characters ">>" at the left margin indicate directions for you to try using a command. For instance: <<Blank lines inserted here by startup of help-with-tutorial>> >> Now type C-v (View next screen) to move to the next screen. (go ahead, do it by depressing the control key and v together). From now on, you'll be expected to do this whenever you finish reading the screen. Note that there is an overlap when going from screen to screen; this provides some continuity when moving through the file. The first thing that you need to know is how to move around from place to place in the file. You already know how to move forward a screen, with C-v. To move backwards a screen, type M-v (which is <ESC>v). >> Try typing M-v and then C-v to move back and forth a few times. SUMMARY ------- The following commands are useful for viewing screenfuls: C-v Move forward one screenful M-v Move backward one screenful C-l Clear screen and redisplay everything putting the text near the cursor at the center. (That's control-L, not control-1. There is no such character as control-1.) >> Find the cursor and remember what text is near it. Then type a C-l. Find the cursor again and see what text is near it now. BASIC CURSOR CONTROL -------------------- Getting from screenful to screenful is useful, but how do you reposition yourself within a given screen to a specific place? There are several ways you can do this. One way (not the best, but the most basic) is to use the commands previous, backward, forward and next. As you can imagine these commands (which are given to AME as C-p, C-b, C-f, and C-n respectively) move the cursor from where it currently is to a new place in the given direction. Here, in a more graphical form are the commands: Previous line, C-p : : Backward, C-b .... Current cursor position .... Forward, C-f : : Next line, C-n >> Move the cursor to the line in the middle of that diagram and type C-l to see the whole diagram centered in the screen. You'll probably find it easy to think of these by letter. P for previous, N for next, B for backward and F for forward. These are the basic cursor positioning commands and you'll be using them ALL the time so it would be of great benefit if you learn them now. In AME, the cursor arrow keys work as well; Cursor Up arrow is previous line, cursor down arrow is next line, cursor left arrow is backward, cursor right arrow is forward. This may be more convenient than using the control sequences. >> Do a few C-n's to bring the cursor down to this line. >> Move into the line with C-f's and then up with C-p's. See what C-p does when the cursor is in the middle of the line. Lines are separated by Newline characters. For most applications there should normally be a Newline character at the end of the text, as well, but it is up to you to make sure of this. A file can validly exist without a Newline at the end. >> Try to C-b at the beginning of a line. Do a few more C-b's. Then do C-f's back to the end of the line and beyond. When you go off the top or bottom of the screen, the text beyond the edge is shifted onto the screen so that your instructions can be carried out while keeping the cursor on the screen. >> Try to move the cursor off the bottom of the screen with C-n and see what happens. If moving by characters is too slow, you can move by words. M-f (Meta-f) moves forward a word and M-b moves back a word. >> Type a few M-f's and M-b's. Intersperse them with C-f's and C-b's. Notice the parallel between C-f and C-b on the one hand, and M-f and M-b on the other hand. Very often Meta characters are used for operations related to English text whereas Control characters operate on the basic textual units that are independent of what you are editing (characters, lines, etc). >> Try a couple of C-a's, and then a couple of C-e's. See how repeated C-a's do nothing. Do you think that this is right? Note: in AME, shift-cursor left acts the same as C-a , and shift-cursor right acts the same as C-e. Two other simple cursor motion commands are M-< (Meta Less-than), which moves to the beginning of the file, and M-> (Meta Greater-than), which moves to the end of the file. You probably don't need to try them, since finding this spot again will be boring. On most terminals the "<" is above the comma and you must use the shift key to type it. On these terminals you must use the shift key to type M-< also; without the shift key, you would be typing M-comma. The location of the cursor in the text is also called "point". To paraphrase, the cursor shows on the screen where point is located in the text. Here is a summary of simple moving operations including the word and sentence moving commands: C-f (Cursor Right) Move forward a character C-b (Cursor Left) Move backward a character M-f Move forward a word M-b Move backward a word C-n (Cursor Down) Move to next line C-p (Cursor Up) Move to previous line C-a (Shift Left) Move to beginning of line C-e (Shift Right) Move to end of line M-< Go to beginning of file M-> Go to end of file >> Try all of these commands now a few times for practice. Since the last two will take you away from this screen, you can come back here with M-v's and C-v's. These are the most often used commands. Like all other commands in AME, these commands can be given arguments which cause them to be executed repeatedly. The way you give a command a repeat count is by typing C-u and then the digits before you type the command. For instance, C-u 8 C-f moves forward eight characters. >> Try giving a suitable argument to C-n or C-p to come as close as you can to this line in one jump. WHEN AME IS HUNG ----------------- If AME gets into an infinite (or simply very long) computation which you don't want to finish, you can stop it safely by typing C-g. You can also use C-g to discard a numeric argument or the beginning of a command that you don't want to finish. >> Type C-u 100 to make a numeric arg of 100, then type C-g. Now type C-f. How many characters does it move? If you have typed an <ESC> by mistake, you can get rid of it with a C-g. WINDOWS ------- AME can have several windows, each displaying its own text. At this stage it is better not to go into the techniques of using multiple windows. But you do need to know how to get rid of extra windows that may appear to display help or output from certain commands. It is simple: C-x 1 One window (i.e., kill all other windows). That is Control-x followed by the digit 1. C-x 1 makes the window which the cursor is in become the full screen, by getting rid of any other windows. >> Move the cursor to this line and type C-u 0 C-l. >> Type ESC-? move See how this window shrinks, while a new one appears to display a listing of the commands that contain move. >> Type C-x 1 and see the help window disappear. INSERTING AND DELETING ---------------------- If you want to insert text, just type it. Characters which you can see, such as A, 7, *, etc. are taken by AME as text and inserted immediately. Type <Return> (the carriage-return key) to insert a Newline character. You can delete the last character you typed by typing <Backspace>. <Backspace> is a key on the keyboard, which is at the top right corner of the keyboard, and is labelled with a left arrow. More generally, <Backspace> deletes the character immediately before the current cursor position. >> Do this now, type a few characters and then delete them by typing <Backspace> a few times. Don't worry about this file being changed; you won't affect the master tutorial. This is just a copy of it. >> Now start typing text until you reach the right margin, and keep typing. When a line of text gets too big for one line on the screen, the line of text is "extended" and is scrolled left. The $ at the right margin indicates a line which has been extended. >> Use <Backspace>s to delete the text until the line fits on one screen line again. The extention line goes away. >> Move the cursor to the beginning of a line and type <Backspace>. This deletes the newline before the line and merges the line onto the previous line. The resulting line may be too long to fit, in which case it has a continuation line. >> Type <Return> to reinsert the Newline you deleted. Remember that most AME commands can be given a repeat count; this includes characters which insert themselves. >> Try that now -- type C-u 8 * and see what happens. You've now learned the most basic way of typing something in AME and correcting errors. You can delete by words or lines as well. Here is a summary of the delete operations: <Backspace> delete the character just before the cursor C-d (or the Delete key) delete the next character after the cursor M-<Backspace> kill the word immediately before the cursor M-d kill the next word after the cursor C-k kill from the cursor position to end of line M-k kill to the end of the current paragraph Notice that <Backspace> and C-d vs M-<Backspace> and M-d extend the parallel started by C-f and M-f (well, <Backspace> isn't really a control character, but let's not worry about that). Now suppose you kill something, and then you decide that you want to get it back? Well, whenever you kill something bigger than a character, AME saves it for you. To yank it back, use C-y. You can kill text in one place, move elsewhere, and then do C-y; this is a good way to move text around. Note that the difference between "Killing" and "Deleting" something is that "Killed" things can be yanked back, and "Deleted" things cannot. Generally, the commands that can destroy a lot of text save it, while the ones that attack only one character, or nothing but blank lines and spaces, do not save. For instance, type C-n a couple times to postion the cursor at some line on this screen. >> Do this now, move the cursor and kill that line with C-k. Note that a single C-k kills the contents of the line, and a second C-k kills the line itself, and make all the other lines move up. If you give C-k a repeat count, it kills that many lines AND their contents. The text that has just disappeared is saved so that you can retrieve it. To retrieve the last killed text and put it where the cursor currently is, type C-y. >> Try it; type C-y to yank the text back. Think of C-y as if you were yanking something back that someone took away from you. Notice that if you do several C-k's in a row the text that is killed is all saved together so that one C-y will yank all of the lines. >> Do this now, type C-k several times. Now to retrieve that killed text: >> Type C-y. Then move the cursor down a few lines and type C-y again. You now see how to copy some text. UNDO ---- Any time you make a change to the text and wish you had not done so, you can undo the change (return the text to its previous state) with the undo command, C-x C-u. Normally, C-x C-u undoes one command's worth of changes; if you repeat the C-x C-u several times in a row, each time undoes one more command. There are two exceptions: commands that made no change (just moved the cursor) do not count, and self-inserting characters are often lumped together in groups of up to 20. This is to reduce the number of C-x C-u's you have to type. >> Kill this line with C-k, then type C-x C-u and it should reappear. Giving a numeric argument to C-_ or C-x u is equivalent to repeating it as many times as the argument says. Undo is controlled by an AME variable; If the above example does not work, you will have to setprefs UNDO. FILES ----- In order to make the text you edit permanent, you must put it in a file. Otherwise, it will go away when your invocation of AME goes away. You put your editing in a file by "finding" the file. What finding means is that you see the contents of the file in your AME; and, loosely speaking, what you are editing is the file itself. However, the changes still don't become permanent until you "save" the file. This is so you can have control to avoid leaving a half-changed file around when you don't want to. Even then, AME leaves the original file under a changed name in case your changes turn out to be a mistake. If you look near the bottom of the screen you will see a reversed line of a different color, and contains the string "AME.01: TUTORIAL". Your copy of the AME tutorial is called "TUTORIAL". Whatever file you find, that file's name will appear in that precise spot. The commands for finding and saving files are unlike the other commands you have learned in that they consist of two characters. They both start with the character Control-x. There is a whole series of commands that start with Control-x; many of them have to do with files, buffers, and related things, and all of them consist of Control-x followed by some other character. Another thing about the command for finding a file is that you have to say what file name you want. We say the command "reads an argument from the terminal" (in this case, the argument is the name of the file). After you type the command C-x C-v Visit a file AME brings up a file requester and asks you to type the file name. When you type <Return> to end the file name, the file requester is no longer needed, so it disappears. >> Type C-x C-v, then click on the cancel button. This cancels the file requester and also cancels the C-x C-r command that was using the requester. So you do not read any file. In a little while the file contents appear on the screen. You can edit the contents. When you wish to make the changes permanent, issue the command C-x C-s Save the file The contents of AME are written into the file. If backups are on, the first time you do this, the original file is renamed to a new name so that it is not lost. The new name is made by appending ".BAK" to the end of the original file's name. When saving is finished, AME prints the number of lines written. You should save fairly often, so that you will not lose very much work if the system should crash. >> Type C-x C-s, saving your copy of the tutorial. This should print "Wrote 761 lines" at the bottom of the screen. To make a new file, just visit it "as if" it already existed. Then start typing in the text. When you ask to "save" the file, AME will really create the file with the text that you have inserted. From then on, you can consider yourself to be editing an already existing file. BUFFERS ------- If you visit a second file with C-x C-v, the first file remains inside AME. You can switch back to it by finding it again with C-x C-v. This way you can get quite a number of files inside AME. The object inside AME which holds the text read from one file is called a "buffer." Finding a file makes a new buffer inside AME. To see a list of the buffers that exist in AME, type C-x C-b List buffers >> Try C-x C-b now. See how each buffer has a name, and it may also have a file name for the file whose contents it holds. Some buffers do not correspond to files. ANY text you see in an AME window has to be in some buffer. >> Type C-x 1 to get rid of the buffer list. If you make changes to the text of one file, then find another file, this does not save the first file. Its changes remain inside AME, in that file's buffer. The creation or editing of the second file's buffer has no effect on the first file's buffer. This is very useful, but it also means that you need a convenient way to save the first file's buffer. It would be a nuisance to have to switch back to it with C-x C-v in order to save it with C-x C-s. So we have C-x C-m Save modified buffers C-x C-m goes through the list of all the buffers you have and finds the ones that contain files you have changed, and saves them. EXTENDING THE COMMAND SET ------------------------- There are many, many more AME commands than could possibly be put on all the control and meta characters. AME gets around this with the eXtended command. This comes in two flavors: C-x Character eXtend. Followed by one character. M-x (or (ESC-ESC) Named command extend. Followed by a long name. These are commands that are generally useful but used less than the commands you have already learned about. You have already seen two of them: the file commands C-x C-v to Find and C-x C-s to Save. Another example is the command to tell AME that you'd like to stop editing and get rid of AME. The command to do this is C-x C-c. (Don't worry; it offers to save each changed file before it kills the AME.) There are many C-x commands. The ones you know are: C-x C-v Visit file. C-x C-s Save file. C-x C-b List buffers. C-x C-c Quit AME. C-x C-u Undo. Named eXtended commands are commands which are used even less frequently, or commands which are used only in certain modes. These commands are usually called "functions". An example is the function findreplace, which globally replaces one string with another. When you type M-x, AME prompts you at the bottom of the screen with M-x and you should type the name of the function you wish to call; in this case, "findreplace". Just type "findr<SPACE>" and AME will complete the name. End the command name with <Return>. Then type the two "arguments"--the string to be replaced, and the string to replace it with--each one ended with a Return. >> Move the cursor to the blank line two lines below this one. Then type M-x findr<SPACE><Return>changed<Return>altered<Return>. Notice how this line has changed: you've replaced the word c-h-a-n-g-e-d with "altered" wherever it occured after the cursor. MODE LINE --------- If AME sees that you are typing commands slowly it shows them to you at the bottom of the screen in an area called the "echo area." The echo area contains the bottom line of the screen. The line immediately above it is called the MODE LINE. The mode line says something like * AME.01 TUTORIAL File: TUTORIAL This is a very useful "information" line. You already know what the second name (the filename) means--it is the file you have found. The other name is the name of this buffer. The AME.01 is the name of the Arexx port. The stars near the front mean that you have made changes to the text. Right after you visit or save a file, there is no star. The part of the mode line at the right is for letters to tell you what modes you are in. The default mode is blank which is what you are in now. It is an example of a "major mode". There are several major modes in AME for editing different languages and text, such as CMODE mode, EXT mode, etc. At any time one and only one major mode is active, and its letter can always be found in the mode line on the right. Each major mode makes a few commands behave differently. For example, there are commands for creating comments in a program, and since each programming language has a different idea of what a comment should look like, each major mode has to insert comments differently. The Setprefs command is used to get into the modes. For example, M-s CMODE is how to get into C mode. If you are going to be editing English text, such as this file, you should probably use normal mode. >> Type M-s C-S CMODE<Return>. Don't worry, none of the commands you have learned changes AME in any great way. Major modes are usually like that: commands don't change into completely unrelated things, but they work a little bit differently. Major modes are called major because there are also minor modes. They are called minor because they aren't alternatives to the major modes, just minor modifications of them. Each minor mode can be turned on or off by itself, regardless of what major mode you are in, and regardless of the other minor modes. So you can use no minor modes, or one minor mode, or any combination of several minor modes. One minor mode which is very useful, especially for editing English text, is WRAP mode. When this mode is on, AME breaks the line in between words automatically whenever the line gets too long. You can turn this mode on by doing M-s WRAP<Return>. When the mode is on, you can turn it off by doing M-s C-s WRAP<Return>. >> Type M-s WRAP<Return> now. Then insert a line of "asdf " over again until you see it divide into two lines. You must put in spaces between them because WRAP breaks lines only at spaces. The margin is usually set at 70 characters, but you can change it with the M-s RIGHT command. You should give the margin setting you want as a number following the RIGHT. >> Type M-s RIGHT 20<Return>. Then type in some text and see AME fill lines of 20 characters with it. Then set the margin back to 70 using M-s RIGHT again. If you makes changes in the middle of a paragraph, WRAP mode does not re-fill it for you. To re-fill the paragraph, type M-j with the cursor inside that paragraph. >> Move the cursor into the previous paragraph and type M-j. SEARCHING --------- AME can do searches for strings (these are groups of contiguous characters or words) either forward through the file or backward through it. To search for the string means that you are trying to locate it somewhere in the file and have AME show you where the occurrences of the string exist. This type of search is somewhat different from what you may be familiar with. It is a search that is performed as you type in the thing to search for. The command to initiate a search is C-s for forward search, and C-r for reverse search. BUT WAIT! Don't do them now. When you type C-s you'll notice that the string "I-search" appears as a prompt in the echo area. This tells you that AME is in what is called an incremental search waiting for you to type the thing that you want to search for. <ESC> terminates a search. >> Now type C-s to start a search. SLOWLY, one letter at a time, type the word 'cursor', pausing after you type each character to notice what happens to the cursor. >> Type C-s to find the next occurrence of "cursor". >> Now type <Backspace> four times and see how the cursor moves. >> Type <ESC> to terminate the search. Did you see what happened? AME, in an incremental search, tries to go to the occurrence of the string that you've typed out so far. To go to the next occurrence of 'cursor' just type C-s again. If no such occurrence exists AME beeps and tells you that it is a failing search. C-g would also terminate the search. If you are in the middle of an incremental search and type <Backspace>, you'll notice that the last character in the search string is erased and the search backs up to the last place of the search. For instance, suppose you currently have typed 'cu' and you see that your cursor is at the first occurrence of 'cu'. If you now type <Backspace>, the 'u' on the search line is erased and you'll be repositioned in the text to the occurrence of 'c' where the search took you before you typed the 'u'. This provides a useful means for backing up while you are searching. If you are in the middle of a search and happen to type a control character (other than a C-s or C-r, which tell AME to search for the next occurrence of the string), the search is terminated. The C-s starts a search that looks for any occurrence of the search string AFTER the current cursor position. But what if you want to search for something earlier in the text? To do this, type C-r for Reverse search. Everything that applies to C-s applies to C-r except that the direction of the search is reversed. GETTING MORE HELP ----------------- In this tutorial we have tried to supply just enough information to get you started using AME. There is so much available in AME that it would be impossible to explain it all here. However, you may want to learn more about AME since it has numerous desirable features that you don't know about yet. AME has some internal documentation, mainly listings of commands and variables. All of these commands can be accessed through the help key and the describekey command (usually accessed by typing F1). The most basic HELP feature is describekey (F1). Type F1, and a command character or sequence, and AME displays the name of the command. >> Type F1 C-p. The message should be something like ^P is bound to moveup This tells you the "name of the function". That is important in writing Arexx code to extend AME; it also is enough to remind you of what the command does if you have seen it before but did not remember. Multi-character commands such as C-x C-s and <ESC>v are also allowed after describekey. HELP Command Apropos. Type in a keyword and AME will list all the commands whose names contain that keyword. These commands can all be invoked with Meta-x. For some commands, Command Apropos will also list a one or two character sequence which has the same effect. >> Type HELP file<Return>. You will see a list of all M-x commands with "file" in their names. You will also see commands like ^X-F and ^X-^I listed beside the command names setfilepath and insertfile. CONCLUSION ---------- Remember, to exit AME permanently use C-x C-c. This tutorial is meant to be understandable to all new users, so if you found something unclear, don't sit and blame yourself - complain! COPYING ------- This tutorial descends from a long line of Emacs tutorials starting with the one written by Stuart Cracraft for the original Emacs. This version of the tutorial, like GNU Emacs, is copyrighted, and comes with permission to distribute copies on certain conditions: Copyright (c) 1985 Free Software Foundation Permission is granted to anyone to make or distribute verbatim copies of this document as received, in any medium, provided that the copyright notice and permission notice are preserved, and that the distributor grants the recipient permission for further redistribution as permitted by this notice. Permission is granted to distribute modified versions of this document, or of portions of it, under the above conditions, provided also that they carry prominent notices stating who last altered them. This tutorial was modified 2/8/93 by Andy Finkel, Flying Cat, Inc. to match the AME editor.