[1X2 Interface to the [10Xncurses[1X Library[0X In this chapter we describe the [5XGAP[0m interface to the [5XGNU[0m [10Xcurses[0m/[10Xncurses[0m [10XC[0m-library. This library contains routines to manipulate the contents of terminal windows. It allows one to write programs which should work on a wide variety of terminal emulations with different sets of capabilities. This technical chapter is intended for readers who want to program new applications using the [10Xncurses[0m functionality. If you are only interested in the function [2XNCurses.BrowseGeneric[0m ([14X4.3-1[0m) from this package or some of its applications you can skip this chapter. Detailed documentation of the [10Xncurses[0m library is probably available in your operating system (try [10Xman ncurses[0m) and from the web (see for example [NCu]). Here, we only give short reminders about the functions provided in the [5XGAP[0m interface and explain how to use the [5XGAP[0m functions. [1X2.1 The [10Xncurses[1X Library[0X In this section we list the functions from the GNU [10Xncurses[0m library and its [10Xpanel[0m extension which are made available in [5XGAP[0m via the [5XBrowse[0m package. See the following section [14X2.2[0m for explanations how to use these functions from within [5XGAP[0m. The basic objects to manipulate are called [13Xwindows[0m, they correspond to rectangular regions of the terminal screen. Windows can overlap but [10Xncurses[0m cannot handle this for the display. Therefore windows can be wrapped in [13Xpanels[0m, they provide a display depth for windows and it is possible to move panels to the top and bottom of the display or to hide a panel. We will not import all the functions of the [10Xncurses[0m library to [5XGAP[0m. For example, there are many pairs of functions with the same name except for a leading [10Xw[0m (like [10Xmove[0m and [10Xwmove[0m for moving the cursor in a window). Here, we only import the versions with [10Xw[0m, which get a window as first argument. The functions without [10Xw[0m are for the [10Xncurses[0m standard screen window [10Xstdscr[0m which is available as window [10X0[0m in [5XGAP[0m. Similarly, there are functions with the same name except for an extra [10Xn[0m (like [10Xwaddstr[0m and [10Xwaddnstr[0m for placing a string into a window). Here, we only import the safer functions with [10Xn[0m which get the number of characters to write as argument. (More convenient functions are then implemented on the [5XGAP[0m level.) [1X2.1-1 Setting the terminal[0X We first list flags for setting the basic behavior of a terminal. With [10Xsavetty[0m/[10Xresetty[0m a setting can be stored and recovered. [8X[10Xsavetty()[0m[8X[0m This stores the current setting of the terminal in a buffer. [8X[10Xresetty()[0m[8X[0m This resets the terminal to what was stored in the last call to [10Xsavetty[0m. [8X [10Xcbreak()/nocbreak()[0m[8X[0m In [10Xcbreak[0m mode each input character from a terminal is directly forwarded to the application (but see [10Xkeypad[0m). With [10Xnocbreak[0m this only happens after a newline or return is typed. [8X[10Xkeypad(win, bool)[0m[8X[0m If set to [9Xtrue[0m some special input like arrow or function keys can be read as single characters from the input (such keys actually generate certain sequences of characters), see also [14X2.1-4[0m. (The [3Xwin[0m argument is irrelevant.) [8X [10Xecho()[0m[8X/[10Xnoecho()[0m[8X[0m This determines if input characters are automatically echoed by the terminal at the current cursor position. [8X[10Xcurs_set(vis)[0m[8X[0m This determines the visibility of the cursor. The argument [3Xvis[0m=0 makes the cursor invisible. With [3Xvis[0m=1 it becomes visible; some terminals allow also higher levels of visibility. [8X[10Xwtimeout(win, delay)[0m[8X[0m Here [3Xdelay[0m determines a timeout in milliseconds for reading characters from the input of a window. Negative values mean infinity, that is a blocking read. [8X [10Xnl()[0m[8X/[10Xnonl()[0m[8X[0m With [10Xnl[0m a return on input is translated to a newline character and a newline on output is interpreted as return and linefeed. [8X[10Xintrflush(win, bool)[0m[8X[0m This flag determines if after an interrupt pending output to the terminal is flushed. (The [3Xwin[0m argument is irrelevant.) [8X[10Xidlok(win, bool)[0m[8X[0m With [9Xtrue[0m the library tries to use a hardware line insertion functionality (in particular for scrolling). [8X[10Xscrollok(win, bool)[0m[8X[0m If set to [9Xtrue[0m moving the cursor down from the last line of a window causes scrolling of the whole window, otherwise nothing happens. [8X[10Xleaveok(win, bool)[0m[8X[0m If set to [9Xtrue[0m a refresh of the window leaves the cursor at its current location, otherwise this is not guaranteed. [8X[10Xclearok(win, bool)[0m[8X[0m If set to [9Xtrue[0m the next refresh of the window will clear the screen completely and redraw everything. [8X[10Ximmedok(win, bool)[0m[8X[0m If set to [9Xtrue[0m all changes of the window will automatically also call a [10Xwrefresh[0m. [8X [10Xraw()[0m[8X/[10Xnoraw()[0m[8X[0m Similar to [10Xcbreak[0m, usually not needed (see the [10Xncurses[0m documentation for details). [1X2.1-2 Manipulating windows[0X In [10Xncurses[0m an arbitrary number of windows which correspond to rectangular regions (maybe overlapping) of the screen can be handled. You should always delete windows which are no longer needed. To get a proper display of overlapping windows (which may occur by recursively called functions using this library) we suggest that you always wrap windows in panels, see [14X2.1-3[0m. For functions which involve coordinates recall that the upper left corner of the screen or internally of any window has the coordinates (0,0). [8X[10Xnewwin(nlines, ncols, y, x)[0m[8X[0m This creates a new window whose upper left corner has the coordinates ([3Xy[0m,[3Xx[0m) on the screen and has [3Xnlines[0m lines and [3Xncols[0m columns, if this is possible. The arguments [3Xnlines[0m and [3Xncols[0m can be zero, then their maximal possible values are assumed. [8X[10Xdelwin(win)[0m[8X[0m Deletes a window. [8X[10Xmvwin(win, y, x)[0m[8X[0m Moves the upper left corner of the window to the given coordinates, if the window still fits on the screen. With panels don't use this function, but use [10Xmove_panel[0m mentioned below. [8X[10Xwrefresh(win)[0m[8X[0m Writing to a window only changes some internal buffers, this function copies the window content to the actual display screen. You don't need this function if you wrap your windows in panels, use [10Xupdate_panels[0m and [10Xdoupdate[0m instead. [8X[10Xdoupdate()[0m[8X[0m Use this function to update the content of your display screen to the current content of all windows. If your terminal is not yet in visual mode this function changes to visual mode. [8X[10Xendwin()[0m[8X[0m Use this function to leave the visual mode of your terminal. (Remark: If you use this function while not in visual mode the cursor will be moved to the line where the visual mode was started last time. To avoid this use [10Xisendwin[0m first.) [8X[10Xisendwin()[0m[8X[0m Returns [9Xtrue[0m if called while not in visual mode and [9Xfalse[0m otherwise [8X[10Xgetbegyx(win)[0m[8X[0m Get the coordinates of the upper left corner of a window on the screen. [8X[10Xgetmaxyx(win)[0m[8X[0m Get the number of lines and columns of a window. [1X2.1-3 Manipulating panels[0X Wrap windows in panels to get a proper handling of overlapping windows on the display. Don't forget to delete a panel before deleting the corresponding window. [8X[10Xnew_panel(win)[0m[8X[0m Create a panel for a window. [8X[10Xdel_panel(pan)[0m[8X[0m Delete a panel. [8X[10Xupdate_panels()[0m[8X[0m Use this function to copy changes of windows and panels to a screen buffer. Then call [10Xdoupdate()[0m to update the display screen. [8X[10Xmove_panel(pan, y, x)[0m[8X[0m Move top left corner of a panel wrapped window to coordinates ([3Xy[0m,[3Xx[0m) if possible. [8X [10Xhide_panel(pan)[0m[8X/[10Xshow_panel(pan)[0m[8X[0m Hide or show, respectively, the content of a panel on the display screen. [8X [10Xtop_panel(pan)[0m[8X/[10Xbottom_panel(pan)[0m[8X[0m Move a panel to the top or bottom of all panels, respectively. [8X [10Xpanel_below(pan)[0m[8X/[10Xpanel_above(pan)[0m[8X[0m Return the panel directly below or above the given one, respectively. With argument [10X0[0m the top or bottom panel are returned, respectively. If argument is the bottom or top panel, respectively, then [9Xfalse[0m is returned. [1X2.1-4 Getting keyboard input[0X If you want to read input from the user first adjust the terminal settings of [10Xcbreak[0m, [10Xkeypad[0m, [10Xecho[0m, [10Xwtimeout[0m and [10Xcurs_set[0m to your needs, see [14X2.1-1[0m. The basic functions are as follows. [8X[10Xwgetch(win)[0m[8X[0m Reads one character from user input (returned as integer). If [10Xwtimeout[0m was set with a positive [3Xdelay[0m then the function returns [9Xfalse[0m if there was no input for [3Xdelay[0m milliseconds. Note that in [10Xnocbreak[0m mode typed characters reach the application only after typing a return. If the [10Xkeypad[0m flag is set to [9Xtrue[0m some special keys can be read like single characters; the keys are explained below. (Note that there is only one input queue for all windows.) [8X[10Xungetch(char)[0m[8X[0m Puts back the character [3Xchar[0m on the input queue. Some terminals allow one to read special keys like one character, we import some of the symbolic names of such keys into [5XGAP[0m. You can check for such characters by comparing with the components of the record [10XNCurses.keys[0m, these are [8X[10XUP[0m[8X/[10XDOWN[0m[8X/[10XLEFT[0m[8X/[10XRIGHT[0m[8X[0m the arrow keys [8X[10XPPAGE[0m[8X/[10XNPAGE[0m[8X[0m the page up and page down keys [8X[10XHOME[0m[8X/[10XEND[0m[8X[0m the home and end keys [8X[10XBACKSPACE[0m[8X/[10XDC[0m[8X[0m the backspace and delete keys [8X[10XIC[0m[8X[0m the insert key [8X[10XENTER[0m[8X[0m the enter key [8X[10XF1[0m[8X/[10XF2[0m[8X/../[10XF24[0m[8X[0m the function keys [8X[10XMOUSE[0m[8X[0m a pseudo key to detect mouse events [8X[10XA1[0m[8X/[10XA3[0m[8X/[10XB2[0m[8X/[10XC1[0m[8X/[10XC3[0m[8X[0m the keys around the arrow keys on a num pad It can happen that on a specific keyboard there is no key for some of these. Also, not all terminals can interpret all of these keys. You can check this with the function [8X[10Xhas_key(key)[0m[8X[0m Checks if the special key [3Xkey[0m is recognized by the terminal. [1X2.1-5 Writing to windows[0X The display of text in [10Xncurses[0m windows has two aspects. The first is to get actual characters on the screen. The second is to specify attributes which influence the display, for example normal or bold fonts or colors. This subsection is for the first aspect. Possible attributes are explained below in [14X2.1-7[0m. [8X[10Xwmove(win, y, x)[0m[8X[0m Moves the cursor to position ([3Xy[0m,[3Xx[0m), recall that the coordinates are zero based, (0,0) being the top left corner. [8X[10Xwaddnstr(win, str, len)[0m[8X[0m Writes the string [3Xstr[0m to the window starting from the current cursor position. Writes at most [3Xlen[0m characters. At end of line the cursor moves to the beginning of next line. The behavior at the end of the window depends on the setting of [10Xscrollok[0m, see [14X2.1-1[0m. [8X[10Xwaddch(win, char)[0m[8X[0m Writes a character to the window at the current cursor position and moves the cursor on. The character [3Xchar[0m is given as integer and can include attribute information. [8X[10Xwborder(win, charlist)[0m[8X[0m Draws a border around the window. If [3Xcharlist[0m is a plain list of eight [5XGAP[0m characters these are taken for left/right/top/bottom sides and top-left/top-right/bottom-left/bottom-right corners. Otherwise default characters are used. (See [2XNCurses.WBorder[0m ([14X2.2-9[0m) for a more user friendly interface.) [8X[10Xwvline(win, char, len)[0m[8X[0m Writes a vertical line of length [3Xlen[0m (or as long as fitting into the window) starting from the current cursor position to the bottom, using the character [3Xchar[0m. If [3Xchar[0m=[10X0[0m the default character is used. [8X[10Xwhline(win, char, len)[0m[8X[0m Same as [10Xwvline[0m but for horizontal lines starting from the cursor position to the right. [8X[10Xwerase(win)[0m[8X[0m Deletes all characters in the window. [8X[10Xwclear(win)[0m[8X[0m Like [10Xwerase[0m, but also calls [10Xclearok[0m. [8X[10Xwclrtobot(win)[0m[8X[0m Deletes all characters from cursor position to the right and bottom. [8X[10Xwclrtoeol(win)[0m[8X[0m Deletes all characters from cursor position to end of line. [8X[10Xwinch(win)[0m[8X[0m Returns the character at current cursor position, as integer and including color and attribute information. [8X[10Xgetyx(win)[0m[8X[0m Returns the current cursor position. [8X[10Xwaddstr(win, str)[0m[8X[0m Delegates to [10Xwaddnstr(win, str, Length(str))[0m. [1X2.1-6 Line drawing characters[0X For drawing lines and grids in a terminal window you should use some "virtual" characters which are available as components of the record [10XNCurses.lineDraw[0m. On some terminals these are nicely displayed as proper lines (on others they are simulated by ASCII characters). These are: [8X[10XBLOCK[0m[8X[0m solid block [8X[10XBOARD[0m[8X[0m board of squares [8X[10XBTEE/LTEE/RTEE/TTEE[0m[8X[0m bottom/left/right/top tee [8X[10XBULLET[0m[8X[0m bullet [8X[10XCKBOARD[0m[8X[0m checker board [8X[10XDARROW/LARROW/RARROW/UARROW[0m[8X[0m down/left/right/up arrow [8X[10XDEGREE[0m[8X[0m degree symbol [8X[10XDIAMOND[0m[8X[0m diamond [8X[10XGEQUAL[0m[8X[0m greater than or equal [8X[10XHLINE/VLINE[0m[8X[0m horizontal/vertical line [8X[10XLANTERN[0m[8X[0m lantern symbol [8X[10XLEQUAL[0m[8X[0m less than or equal [8X[10XLLCORNER/LRCORNER/ULCORNER/URCORNER[0m[8X[0m lower left/lower right/upper left/upper right corner [8X[10XNEQUAL[0m[8X[0m not equal [8X[10XPI[0m[8X[0m letter pi [8X[10XPLMINUS[0m[8X[0m plus-minus [8X[10XPLUS[0m[8X[0m crossing lines like a plus [8X[10XS1/S3/S7/S9[0m[8X[0m scan line 1/3/7/9 [8X[10XSTERLING[0m[8X[0m pound sterling [1X2.1-7 Text attributes and colors[0X In addition to the actual characters to be written to the screen the way they are displayed can be changed by additional [13Xattributes[0m. (There should be no danger to mix up this notion of attributes with the one introduced in [14X'Reference: Attributes'[0m.) The available attributes are stored in the record [10XNCurses.attrs[0m, they are [8X[10XNORMAL[0m[8X[0m normal display with no extra attributes. [8X[10XSTANDOUT[0m[8X[0m displays text in the best highlighting mode of the terminal. [8X[10XUNDERLINE[0m[8X[0m underlines the text. [8X[10XREVERSE[0m[8X[0m display in reverse video by exchanging the foreground and background color. [8X[10XBLINK[0m[8X[0m displays the text blinking. [8X[10XDIM[0m[8X[0m displays the text half bright. [8X[10XBOLD[0m[8X[0m displays the text in a bold font. Note that not all of these work with all types of terminals, or some may cause the same display. Furthermore, if [10XNCurses.attrs.has_colors[0m is [9Xtrue[0m there is a list [10XNCurses.attrs.ColorPairs[0m of attributes to set the foreground and background color. These should be accessed indirectly with [2XNCurses.ColorAttr[0m ([14X2.2-1[0m). Attributes can be combined by adding their values (internally, they are represented by integers). They can also be added to the integer representing a character for use with [10Xwaddch[0m. The library functions for setting attributes are: [8X[10Xwattrset(win, attr)[0m[8X[0m This sets the default (combined) attributes for a window which is added to all characters written to it; using [10XNCurses.attrs.NORMAL[0m as attribute is a reset. [8X [10Xwattron(win, attr)[0m[8X/[10Xwattroff(win, attr)[0m[8X[0m This sets or unsets one or some default attributes of the window without changing the others. [8X[10Xwattr_get(win)[0m[8X[0m This returns the current default attribute and default color pair of a window. [8X[10Xwbkgdset(win, attr)[0m[8X[0m This is similar to [10Xwattrset[0m but you can also add a character to [3Xattr[0m which is used as default instead of blanks. [8X[10Xwbkgd(win, attr)[0m[8X[0m This function changes the attributes for all characters in the window to [3Xattr[0m, also used for further characters written to that window. [1X2.1-8 Low level [10Xncurses[1X mouse support[0X Many [10Xxterm[0m based terminals support mouse events. The recognition of mouse events by the [10Xncurses[0m input queue can be switched on and off. If switched on and a mouse event occurs, then [10XNCurses.wgetch[0m gets [10XNCurses.keys.MOUSE[0m if the [10Xkeypad[0m flag is [9Xtrue[0m (see [14X2.1-4[0m). If this is read one must call [10XNCurses.getmouse[0m which reads further characters from the input queue and interprets them as details on the mouse event. In most cases the function [2XNCurses.GetMouseEvent[0m ([14X2.2-10[0m) can be used in applications (it calls [10XNCurses.getmouse[0m). The following low level functions are available as components of the record [10XNCurses[0m. The names of mouse events which may be possible are stored in the list [10XNCurses.mouseEvents[0m, which starts [10X[[0m [10X"BUTTON1_PRESSED",[0m [10X"BUTTON1_RELEASED",[0m [10X"BUTTON1_CLICKED",[0m [10X"BUTTON1_DOUBLE_CLICKED",[0m [10X"BUTTON1_TRIPLE_CLICKED",[0m [10X...[0m and contains the same for buttons number 2 to 5 and a few other events. [8X [10Xmousemask(intlist)[0m[8X[0m The argument [3Xintlist[0m is a list of integers specifying mouse events. An entry [10Xi[0m refers to the event described in [10XNCurses.mouseEvents[i+1][0m. It returns a record with components [10X.new[0m (for the current setting) and [10X.old[0m (for the previous setting) which are again lists of integers with the same meaning. Note that [10X.new[0m may be different from [3Xintlist[0m, it is always the empty list if the terminal does not support mouse events. In applications use [2XNCurses.UseMouse[0m ([14X2.2-10[0m) instead of this low level function. [8X [10Xgetmouse()[0m[8X[0m This function must be called after a key [10XNCurses.keys.MOUSE[0m was read. It returns a list with three entries [10X[y, x, intlist][0m where [10Xy[0m and [10Xx[0m are the coordinates of the character cell where the mouse event occured and [10Xintlist[0m describes the event, it should have length one and refers to a position in [10XNCurses.mouseEvents[0m. [8X [10Xwenclose(win, y, x)[0m[8X[0m This functions returns [9Xtrue[0m if the screen position [3Xy[0m, [3Xx[0m is within window [3Xwin[0m and [9Xfalse[0m otherwise. [8X [10Xmouseinterval(t)[0m[8X[0m Sets the time to recognize a press and release of a mouse button as a click to [3Xt[0m milliseconds. (Note that this may have no effect because a window manager may catch this.) [1X2.1-9 Miscellaneous function[0X We also provide the [10Xncurses[0m function [10Xmnap(msec)[0m which is a sleep for [3Xmsec[0m milliseconds. [1X2.2 The [10Xncurses[1X [5XGAP[1X functions[0X The functions of the [10Xncurses[0m library are used within [5XGAP[0m very similarly to their [10XC[0m equivalents. The functions are available as components of a record [10XNCurses[0m with the name of the [10XC[0m function (e.g., [10XNCurses.newwin[0m). In [5XGAP[0m the [10Xncurses[0m windows are accessed via integers (as returned by [10XNCurses.newwin[0m). The standard screen [10Xstdscr[0m from the [10Xncurses[0m library is available as window number [10X0[0m. But this should not be used; to allow recursive applications of [10Xncurses[0m always create a new window, wrap it in a panel and delete both when they are no longer needed. Each window can be wrapped in one panel which is accessed by the same integer. (Window [10X0[0m cannot be used with a panel.) Coordinates in windows are the same zero based integers as in the corresponding [10XC[0m functions. The interface of functions which [13Xreturn[0m coordinates is slightly different from the [10XC[0m version; they just return lists of integers and you just give the window as argument, e.g., [10XNCurses.getmaxyx(win)[0m returns a list [10X[nrows, ncols][0m of two integers. Characters to be written to a window can be given either as [5XGAP[0m characters like [10X'a'[0m or as integers like [10XINT_CHAR('a') = 97[0m. If you use the integer version you can also add attributes including color settings to it for use with [10XNCurses.waddch[0m. When writing an application decide about an appropriate terminal setting for your visual mode windows, see [14X2.1-1[0m and the utility function [2XNCurses.SetTerm[0m ([14X2.2-2[0m) below. Use [10XNCurses.savetty()[0m and [10XNCurses.resetty()[0m to save and restore the previous setting. We also provide some higher level functionality for displaying marked up text, see [2XNCurses.PutLine[0m ([14X2.2-6[0m) and [2XNCurses.IsAttributeLine[0m ([14X2.2-3[0m). We now describe some utility functions for putting text on a terminal window. [1X2.2-1 NCurses.ColorAttr[0m [2X> NCurses.ColorAttr( [0X[3Xfgcolor, bgcolor[0X[2X ) ____________________________[0Xfunction [6XReturns:[0X an attribute for setting the foreground and background color to be used on a terminal window (it is a [5XGAP[0m integer). [2X> NCurses.attrs.has_colors___________________________________[0Xglobal variable The return value can be used like any other attribute as described in [14X2.1-7[0m. The arguments [3Xfgcolor[0m and [3Xbgcolor[0m can be given as strings, allowed are those in [10X[ "black", "red", "green", "yellow", "blue", "magenta", "cyan", "white" ][0m. These are the default foreground colors 0 to 7 on ANSI terminals. Alternatively, the numbers 0 to 7 can be used directly as arguments. Note that terminals can be configured in a way such that these named colors are not the colors which are actually displayed. The variable [2XNCurses.attrs.has_colors[0m is set to [9Xtrue[0m or [9Xfalse[0m if the terminal supports colors or not, respectively. If a terminal does not support colors then [2XNCurses.ColorAttr[0m always returns [10XNCurses.attrs.NORMAL[0m. For an attribute setting the foreground color with the default background color of the terminal use [10X-1[0m as [3Xbgcolor[0m or the same as [3Xfgcolor[0m. [4X--------------------------- Example ----------------------------[0X [4Xgap> win := NCurses.newwin(0,0,0,0);; pan := NCurses.new_panel(win);;[0X [4Xgap> defc := NCurses.defaultColors;;[0X [4Xgap> NCurses.wmove(win, 0, 0);;[0X [4Xgap> for a in defc do for b in defc do[0X [4X> NCurses.wattrset(win, NCurses.ColorAttr(a, b));[0X [4X> NCurses.waddstr(win, Concatenation(a,"/",b,"\t"));[0X [4X> od; od;[0X [4Xgap> NCurses.update_panels();; NCurses.doupdate();;[0X [4Xgap> NCurses.napms(5000); # show for 5 seconds[0X [4Xgap> NCurses.endwin();; NCurses.del_panel(pan);; NCurses.delwin(win);;[0X [4X------------------------------------------------------------------[0X [1X2.2-2 NCurses.SetTerm[0m [2X> NCurses.SetTerm( [0X[3X[record][0X[2X ) ______________________________________[0Xfunction This function provides a unified interface to the various terminal setting functions of [10Xncurses[0m listed in [14X2.1-1[0m. The optional argument is a record with components which are assigned to [9Xtrue[0m or [9Xfalse[0m. Recognised components are: [10Xcbreak[0m, [10Xecho[0m, [10Xnl[0m, [10Xintrflush[0m, [10Xleaveok[0m, [10Xscrollok[0m, [10Xkeypad[0m, [10Xraw[0m (with the obvious meaning if set to [9Xtrue[0m or [9Xfalse[0m, respectively). The default, if no argument is given, is [10Xrec(cbreak := true, echo := false, nl := false, intrflush := false, leaveok := true, scrollok := false, keypad := true)[0m. (This is a useful setting for many applications.) If there is an argument [3Xrecord[0m, then the given components overwrite the corresponding defaults. [1X2.2-3 NCurses.IsAttributeLine[0m [2X> NCurses.IsAttributeLine( [0X[3Xobj[0X[2X ) ___________________________________[0Xfunction [6XReturns:[0X [9Xtrue[0m if the argument describes a string with attributes. An [13Xattribute line[0m describes a string with attributes. It is represented by either a string or a dense list of strings, integers, and Booleans immediately following integers, where at least one list entry must [13Xnot[0m be a string. (The reason is that we want to be able to distinguish between an attribute line and a list of such lines, and that the case of plain strings is perhaps the most usual one, so we do not want to force wrapping each string in a list.) The integers denote attribute values such as color or font information, the Booleans denote that the attribute given by the preceding integer is set or reset. If an integer is not followed by a Boolean then it is used as the attribute for the following characters, that is it overwrites all previously set attributes. Note that in some applications the variant with explicit Boolean values is preferable, because such a line can nicely be highlighted just by prepending a [10XNCurses.attrs.STANDOUT[0m attribute. For an overview of attributes, see [14X2.1-7[0m. [4X--------------------------- Example ----------------------------[0X [4Xgap> NCurses.IsAttributeLine( "abc" );[0X [4Xtrue[0X [4Xgap> NCurses.IsAttributeLine( [ "abc", "def" ] );[0X [4Xfalse[0X [4Xgap> NCurses.IsAttributeLine( [ NCurses.attrs.UNDERLINE, true, "abc" ] );[0X [4Xtrue[0X [4Xgap> NCurses.IsAttributeLine( "" ); NCurses.IsAttributeLine( [] );[0X [4Xtrue[0X [4Xfalse[0X [4X------------------------------------------------------------------[0X The [13Xempty string[0m is an attribute line whereas the [13Xempty list[0m (which is not in [2XIsStringRep[0m ([14XReference: IsStringRep[0m)) is [13Xnot[0m an attribute line. [1X2.2-4 NCurses.ConcatenationAttributeLines[0m [2X> NCurses.ConcatenationAttributeLines( [0X[3Xlines[, keep][0X[2X ) _____________[0Xfunction [6XReturns:[0X an attribute line. For a list [3Xlines[0m of attribute lines (see [2XNCurses.IsAttributeLine[0m ([14X2.2-3[0m)), [10XNCurses.ConcatenationAttributeLines[0m returns the attribute line obtained by concatenating the attribute lines in [3Xlines[0m. If the optional argument [3Xkeep[0m is [9Xtrue[0m then attributes set in an entry of [3Xlines[0m are valid also for the following entries of [3Xlines[0m. Otherwise (in particular if there is no second argument) the attributes are reset to [10XNCurses.attrs.NORMAL[0m between the entries of [3Xlines[0m. [4X--------------------------- Example ----------------------------[0X [4Xgap> plain_str:= "hello";;[0X [4Xgap> with_attr:= [ NCurses.attrs.BOLD, "bold" ];;[0X [4Xgap> NCurses.ConcatenationAttributeLines( [ plain_str, plain_str ] );[0X [4X"hellohello"[0X [4Xgap> NCurses.ConcatenationAttributeLines( [ plain_str, with_attr ] );[0X [4X[ "hello", 2097152, "bold" ][0X [4Xgap> NCurses.ConcatenationAttributeLines( [ with_attr, plain_str ] );[0X [4X[ 2097152, "bold", 0, "hello" ][0X [4Xgap> NCurses.ConcatenationAttributeLines( [ with_attr, with_attr ] );[0X [4X[ 2097152, "bold", 0, 2097152, "bold" ][0X [4Xgap> NCurses.ConcatenationAttributeLines( [ with_attr, with_attr ], true );[0X [4X[ 2097152, "bold", 2097152, "bold" ][0X [4X------------------------------------------------------------------[0X [1X2.2-5 NCurses.RepeatedAttributeLine[0m [2X> NCurses.RepeatedAttributeLine( [0X[3Xline, width[0X[2X ) _____________________[0Xfunction [6XReturns:[0X an attribute line. For an attribute line [3Xline[0m (see [2XNCurses.IsAttributeLine[0m ([14X2.2-3[0m)) and a positive integer [3Xwidth[0m, [10XNCurses.RepeatedAttributeLine[0m returns an attribute line with [3Xwidth[0m displayed characters (see [2XNCurses.WidthAttributeLine[0m ([14X2.2-7[0m)) that is obtained by concatenating sufficiently many copies of [3Xline[0m and cutting off a tail if applicable. [4X--------------------------- Example ----------------------------[0X [4Xgap> NCurses.RepeatedAttributeLine( "12345", 23 );[0X [4X"12345123451234512345123"[0X [4Xgap> NCurses.RepeatedAttributeLine( [ NCurses.attrs.BOLD, "12345" ], 13 );[0X [4X[ 2097152, "12345", 0, 2097152, "12345", 0, 2097152, "123" ][0X [4X------------------------------------------------------------------[0X [1X2.2-6 NCurses.PutLine[0m [2X> NCurses.PutLine( [0X[3Xwin, y, x, lines[, skip][0X[2X ) ______________________[0Xfunction [6XReturns:[0X [9Xtrue[0m if [3Xlines[0m were written, otherwise [9Xfalse[0m. The argument [3Xlines[0m can be a list of attribute lines (see [2XNCurses.IsAttributeLine[0m ([14X2.2-3[0m)) or a single attribute line. This function writes the attribute lines to window [3Xwin[0m at and below of position [3Xy[0m, [3Xx[0m. If the argument [3Xskip[0m is given, it must be a nonnegative integer. In that case the first [3Xskip[0m characters of each given line are not written to the window (but the attributes are). [1X2.2-7 NCurses.WidthAttributeLine[0m [2X> NCurses.WidthAttributeLine( [0X[3Xline[0X[2X ) _______________________________[0Xfunction [6XReturns:[0X number of displayed characters in an attribute line. For an attribute line [3Xline[0m (see [2XNCurses.IsAttributeLine[0m ([14X2.2-3[0m)), the function returns the number of displayed characters of [3Xline[0m. [4X--------------------------- Example ----------------------------[0X [4Xgap> NCurses.WidthAttributeLine( "abcde" );[0X [4X5[0X [4Xgap> NCurses.WidthAttributeLine( [ NCurses.attrs.BOLD, "abc",[0X [4X> NCurses.attrs.NORMAL, "de" ] );[0X [4X5[0X [4X------------------------------------------------------------------[0X [1X2.2-8 NCurses.Grid[0m [2X> NCurses.Grid( [0X[3Xwin, trow, brow, lcol, rcol, rowinds, colinds[0X[2X ) ____[0Xfunction This function draws a grid of horizontal and vertical lines on the window [3Xwin[0m, using the line drawing characters explained in [14X2.1-6[0m. The given arguments specify the top and bottom row of the grid, its left and right column, and lists of row and column numbers where lines should be drawn. [4X--------------------------- Example ----------------------------[0X [4Xgap> fun := function() local win, pan;[0X [4X> win := NCurses.newwin(0,0,0,0);[0X [4X> pan := NCurses.new_panel(win);[0X [4X> NCurses.Grid(win, 2, 11, 5, 22, [5, 6], [13, 14]);[0X [4X> NCurses.PutLine(win, 12, 0, "Press <Enter> to quit");[0X [4X> NCurses.update_panels(); NCurses.doupdate();[0X [4X> NCurses.wgetch(win);[0X [4X> NCurses.endwin();[0X [4X> NCurses.del_panel(pan); NCurses.delwin(win);[0X [4X> end;;[0X [4Xgap> fun();[0X [4X------------------------------------------------------------------[0X [1X2.2-9 NCurses.WBorder[0m [2X> NCurses.WBorder( [0X[3Xwin[, chars][0X[2X ) __________________________________[0Xfunction This is a convenient interface to the [10Xncurses[0m function [10Xwborder[0m. It draws a border around the window [3Xwin[0m. If no second argument is given the default line drawing characters are used, see [14X2.1-6[0m. Otherwise, [3Xchars[0m must be a list of [5XGAP[0m characters or integers specifying characters, possibly with attributes. If [3Xchars[0m has length 8 the characters are used for the left/right/top/bottom sides and top-left/top-right/bottom-left/bottom-right corners. If [3Xchars[0m contains 2 characters the first is used for the sides and the second for all corners. If [3Xchars[0m contains just one character it is used for all sides including the corners. [1X2.2-10 Mouse support in [10Xncurses[1X applications[0X [2X> NCurses.UseMouse( [0X[3Xon[0X[2X ) ___________________________________________[0Xfunction [6XReturns:[0X a record [2X> NCurses.GetMouseEvent( [0X[3X[0X[2X ) ________________________________________[0Xfunction [6XReturns:[0X a list of records [10Xncurses[0m allows on some terminals ([10Xxterm[0m and related) to catch mouse events. In principle a subset of events can be catched, see [10Xmousemask[0m in [14X2.1-8[0m. But this does not seem to work well with proper subsets of possible events (probably due to intermediate processes X, window manager, terminal application, ...). Therefore we suggest to catch either all or no mouse events in applications. This can be done with [2XNCurses.UseMouse[0m with argument [9Xtrue[0m to switch on the recognition of mouse events and [9Xfalse[0m to switch it off. The function returns a record with components [10X.new[0m and [10X.old[0m which are both set to the status [9Xtrue[0m or [9Xfalse[0m from after and before the call, respectively. (There does not seem to be a possibility to get the current status without calling [2XNCurses.UseMouse[0m.) If you call the function with argument [9Xtrue[0m and the [10X.new[0m component of the result is [9Xfalse[0m, then the terminal does not support mouse events. When the recognition of mouse events is switched on and a mouse event occurs then the key [10XNCurses.keys.MOUSE[0m is found in the input queue, see [10Xwgetch[0m in [14X2.1-4[0m. If this key is read the low level function [10XNCurses.getmouse[0m must be called to fetch further details about the event from the input queue, see [14X2.1-8[0m. In many cases this can be done by calling the function [2XNCurses.GetMouseEvent[0m which also generates additional information. The return value is a list of records, one for each panel over which the event occured, these panels sorted from top to bottom (so, often you will just need the first entry if there is any). Each of these records has components [10X.win[0m, the corresponding window of the panel, [10X.y[0m and [10X.x[0m, the relative coordinates in window [10X.win[0m where the event occured, and [10X.event[0m, which is bound to one of the strings in [10XNCurses.mouseEvents[0m which describes the event. [13XSuggestion:[0m Always make the use of the mouse optional in your application. Allow the user to switch mouse usage on and off while your application is running. Some users may not like to give mouse control to your application, for example the standard cut and paste functionality cannot be used while mouse events are catched. [1X2.2-11 NCurses.SaveWin[0m [2X> NCurses.SaveWin( [0X[3Xwin[0X[2X ) ___________________________________________[0Xfunction [2X> NCurses.StringsSaveWin( [0X[3Xcont[0X[2X ) ___________________________________[0Xfunction [2X> NCurses.RestoreWin( [0X[3Xwin, cont[0X[2X ) __________________________________[0Xfunction [2X> NCurses.ShowSaveWin( [0X[3Xcont[0X[2X ) ______________________________________[0Xfunction [6XReturns:[0X a [5XGAP[0m object describing the contents of a window. These functions can be used to save and restore the contents of [10Xncurses[0m windows. [2XNCurses.SaveWin[0m returns a list [10X[nrows, ncols, chars][0m giving the number of rows, number of columns, and a list of integers describing the content of window [3Xwin[0m. The integers in the latter contain the displayed characters plus the attributes for the display. The function [2XNCurses.StringsSaveWin[0m translates data [3Xcont[0m in form of the output of [2XNCurses.SaveWin[0m to a list of [10Xnrows[0m strings giving the text of the rows of the saved window, and ignoring the attributes. You can view the result with [2XNCurses.Pager[0m ([14X3.1-4[0m). The argument [3Xcont[0m for [2XNCurses.RestoreWin[0m must be of the same format as the output of [2XNCurses.SaveWin[0m. The content of the saved window is copied to the window [3Xwin[0m, starting from the top-left corner as much as it fits. The utility [2XNCurses.ShowSaveWin[0m can be used to display the output of [2XNCurses.SaveWin[0m (as much of the top-left corner as fits on the screen).