Artifact 388cd68bdd5f9ee8b647ceb0ae1e9788615853fa46cebebcf2e241b674f59e8e:
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psl-1983/3-1/doc/nmode/nm-display.ibm
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— Add Reduce 3.0 to the historical section of the archive, and some more
files relating to version sof PSL from the early 1980s. Thanks are due to
Paul McJones and Nelson Beebe for these, as well as to all the original
authors.git-svn-id: https://svn.code.sf.net/p/reduce-algebra/code/historical@5328 2bfe0521-f11c-4a00-b80e-6202646ff360 (user: arthurcnorman@users.sourceforge.net, size: 8692) [annotate] [blame] [check-ins using] [more...]
,MOD - R 44X (11 April 1983) <PSL.NMODE-DOC>NM-DISPLAY.ibm PLA 97_LAS 80 0_FIR 2_INT 1 6.0_TYP 160 163 162 193_INP 12 101_MAR 2 ,END ,PRO 201 OUT 160_202 OUT 163_203 OUT 162_204 OUT 193 205 INP 12 101_206 INP 12 102 ,END ,DEFINE UNIT SPACE FUNCTION ,END 201/NMODE Manual (Controlling the Display) Page 17-1 202/17. Controlling the Display 201/Since only part of a large file fits on the screen, NMODE tries to show the part that is likely to be interesting. The display control commands allow you to ask to see a different part of the file. C-L Clear and redisplay screen, putting point at a specified vertical position. ESC-J Clear and rewrite display, but without moving text or point. C-V Scroll forwards (a screen or a few lines). M-V Scroll backwards. M-R Move point to the text at a given vertical position. C-M-R Shift the function point is in onto the screen. ESC-S scroll window up line ESC-T scroll window down line ESC-U scroll window up page ESC-V scroll window down page C-X < scroll window left C-X > scroll window right The terminal screen is rarely large enough to display all of your file. If the whole buffer doesn't fit on the screen, NMODE shows a contiguous portion of it, containing point. It continues to show approximately the same portion until point moves outside of it; then NMODE chooses a new portion centered around the new point. This is NMODE's guess as to what you are most interested in seeing. But if the guess is wrong, you can use the display control commands to see a different portion. The finite area of screen through which you can see part of the buffer is called 202/the window201/, and the choice of where in the buffer to start displaying is also called 202/the window201/. The basic display control command is C-L (203/nmode-refresh-command201/). In its simplest form, with no argument, it clears the screen and tells NMODE to choose a new window position. If enough of the buffer is above point, NMODE will pick the window's position in the file so that point is about two-thirds of the way down the screen. If there is not enough of the buffer above point to fill up two-thirds of the screen, NMODE will pick the window position so that point is one-third of the way down the screen. If there isn't even enough of the buffer above point to fill a third of the screen, NMODE will put the top of the buffer at the top of the screen and let point fall where it may. Another command that can be used to help clear up the screen is ESC-J (203/nmode-full-refresh201/). This clears and rewrites the display, but without changing the portion of the buffer displayed on the screen. C-L with a positive argument chooses a new window so as to put point that many lines from the top. An argument of zero puts point on the very top line. Point does not move with respect to the text; rather, the text and point move rigidly on the screen. C-L with a negative argument puts point that many lines from the bottom of the window. For example, C-U -1 C-L puts point on the bottom line, and C-U -5 C-L puts it five lines from the bottom. C-L with an argument does not clear the screen, so that it can move the text on the screen instead of printing it again if the terminal allows that. 201/Page 17-2 NMODE Manual (Controlling the Display) The 202/scrolling 201/commands C-V and M-V let you move the whole display up or down a few lines. C-V (203/next-screen-command201/) with an argument shows you that many more lines at the bottom of the screen, moving the text and point up together as C-L might. C-V with a negative argument shows you more lines at the top of the screen, as does Meta-V (203/previous-screen-command201/) with a positive argument. There are two other commands that let you move the whole display up or down by a few lines. These are ESC-S (203/scroll-window-up-line-command201/) and ESC-T (203/scroll-window-down-line-command201/). These move text and point together up and down respectively relative to the screen. To read the buffer a screenful at a time, use the C-V command with no argument. Each C-V shows the "next screenful" of text. Point is put at the same point on the screen as on the previous screen. To move backward, use M-V without an argument, which moves a whole screenful backwards. To move by multiple screenfuls in the buffer, ESC-U (203/scroll-window-up-page-command201/) and ESC-V (203/scroll-window-down-page-command201/) can be used. These functions accept command arguments and then move the text in the screen up or down by command-argument pages. They will reverse direction if given negative arguments. In Lisp mode, one can use the C-M-R command (203/reposition-window-command201/) to scroll the buffer so that the current function (defun) is positioned conveniently on the screen. This command tries to get as much as possible of the current function, preferring the beginning to the end, but not moving point off the screen. There are also commands to scroll the window horizontally. C-X < (203/scroll-window-left-command201/) and C-X > (203/scroll-window-right-command201/). These scroll the portion of the buffer viewed by the screen to the left or right respectively. These commands have the opposite movement conventions from the other scrolling commands. In all the other commands, one gets the correct direction of movement by imagining that it is the characters visible on the CRT that are moving. For these commands one should think of the screen as a movable hole looking at the buffer, and it is the movement of the hole that is named by the commands. C-L in all its forms changes the position of point on the screen, carrying the text with it. Another command moves point the same way but leaves the text fixed. It is called Meta-R (203/move-to-screen-edge-command201/). With no argument, it puts point in the line at the center of the screen, at the current vertical column. An argument is used to specify the line to put it on, counting from the top if the argument is positive, or from the bottom if it is negative. Thus, Meta-R with an argument of 0 puts point on the top line of the screen. Meta-R never causes any text to move on the screen; it causes point to move with respect to the screen and the text.