j1m: переводы

→s := <- ctnd =>
case s[0] {
'0' => exit
}
}

→Program Listing 3-16 tkgreet.b
1 implement TkGreet;
2
3 include "sys.m";
4 include "draw.m";
5 include "tk.m";
6 include "wmlib.m";
7
8 sys: sys;
9 tk: Tk;
10 wmlib: wmlib;
11 msg: string;
12
13 TkGreet : module {
14 init: fn(ctxt: ref Draw->context, argv: list of string);
15 };
16
17 init(ctxt: ref Draw->context, argv: list of string) {
18 sys = load sys Sys->PATH;
19 tk = load Tk Tk->PATH;
20 wmlib = load Wtnlib Wmlib->PATH;
21 wmlib->init(); 22
23 if ((tl argv) != nil)
24 tnsg = "Hello, " + (hd(t1 argv)) + "!";
25 else
26 tnsg = "Hello, world!";
27
28 win_cfg := array [] of {
29 "label .i -bitmap @/icons/logon.bit",
30 "label .t -text {" + msg + "\n" + "}",
31 "focus .t",
32 "button .b -text {OK} -width lOh -command {send cmd o}",
33 "pack .i .t .b -padx 5 -pady 5",
34 "pack propagate . 0",
35 "update",
36 };
37
38 (title, menubut) := wmlib->tit1ebar(ctxt. screen, "-x 50 -y 25", "Limbo/Tk Example", wmlib->Hide); 39
40 cmd := chan of string;
41 tk->namechan(tit1e, cmd, "cmd"); 42
43 wmlib->tkcmds(tit1e, win_cfg);
44
45 for(;;) alt {
46 click := <- menubut =>
47 if (click[0] == 'e')
48 return;
49 wmlib->tit1ectl (title, click);
50 if (click[0] == 't')
57 tk->cmd(tit1e, "focus .t");

→The following is the version of Greet program that simply illustrates the use of the Limbo/Tk modules:

→The standard Inferno distribution includes the window manager prototype, wm, and the Wmlib module (wml i b. m). The Wmlib module simplifies both the processing of Limbo/Tk commands and the construction of windowed applications.

→The topi evel function creates a window. It returns the Topi evel type that can be passed to other Limbo/Tk functions.

→Applications should allocate an El ement only through the appropriate member functions. Moreover, except where indicated, applications should not modify the data members directly. Although the type definitions make data members visible, the members should be treated as read-only data.

→The objects on the screen are of type Compound, each of which occupies a unique window on the display and contains objects of type El ement. An El ement may be a single object or a list of El ements that can be used to build structured components.

→Those that are familiar with Ousterhout’s Tcl and the Tk Toolkit, commonly Tcl/Tk, will find Limbo/Tk to be very similar. However, Limbo/Tk does not implement all of the features of Tk 4.0. For more information about the differences between Limbo/Tk and Tk 4.0, see the Inferno Reference Manual.

→EText A single line of text. Text for this element is drawn with style.textfont and style.textcolor.
ETitle A single line of text, usually giving the title of a compound ject. Text for this element is drawn with style.titlefont and style.titlecolor.
Eicon An image object.
ESeparator An image object, like an Eicon, but intended to fill space in a list, rather than to serve as an element of the list. An ESeparator is ignored when selecting or highlighting list elements.
EHorizontal A horizontal list of elements.
EVertical A vertical list of elements.

→The Prefab module defines elements as the graphic components. There are six types of Prefab elements, as described in Table 3-6.
Table 3-6 Prefab Elements

→Applications should allocate a Compound only through the appropriate member functions. Moreover, except where indicated, applications should not modify the data members directly. Although the type definitions make data members visible, the members should be treated as read-only data.

→After the Compound is built, Compound .draw must be called to make it visible. Compounds have a border around them, drawn in Styl e. edgecol or and contain, from top-to-bottom:
■ the title (if any)
■ a horizontal line (if there is a title)
■ the contents

→The type Compound defines boxes drawn on the screen. Each appears in a new window, Compound. i mage, and holds a (possibly ni 1) ti tl e and contents. It occupies the space on the screen defined by Compound. r. Allocating a Compound creates a window but does not draw it.

→The Prefab module, as a graphics “toolkit,” provides higher-level graphics capabilities compared to the Draw module. There are still concepts and terms that should be introduced first.

→After compiling this program, you could run it from the Inferno console (not from a shell under Window Manager):
infernoS drawgreet inferno

→Line 42 draws the display area (the rectangle specified by di sp. r) using the color whi te. Line 43 draws the bitmap image, i mg, on the display. Line 44 draws the text in str using font. Line 45 pauses before the display is cleared, Line 46.

→Line 23 refreshes the display just allocated using the recommended technique of spawning a local function, refresh (Lines 49 through 51) that calls the Di spl ay. startref resh function in the Draw module.

→The Font type defines the appearance of characters drawn with the Image. font function. Fonts are read from files that describe their size, style, and the portion of the Unicode character set they represent. Line 27 opens a font file, uni code. 9x24. font, in the /f onts/ 1 uci dasans/ directory and assigns it to font.

→The Image type provides the basic operations for a group of pixels and the building blocks for higher-level objects such as pictures (graphic image files), windows, and fonts. Line 22 assigns the visible contents (the Draw canvas) to di sp. Line 37 opens a bitmap image, 1 ogon. bi t, in the /i cons/ directory and assigns it to i mg.

→Line 7 declares the handle to the Draw module and Line 8 imports the Draw data structures into the current scope. Of particular note are the Di spl ay, Image, and Font types.
The Di spl ay type represents the physical display represented by the draw device mounted in /dev/draw. Line 21 allocates this display using the Di spl ay. al 1 ocate function (the default is specified by the empty string argument ni 1).