1%D \module 2%D [ file=mult-ini, 3%D version=2008.10.22, % 1996.06.01, 4%D title=\CONTEXT\ Multilingual Macros, 5%D subtitle=Initialization, 6%D author=Hans Hagen, 7%D date=\currentdate, 8%D copyright={PRAGMA ADE \& \CONTEXT\ Development Team}] 9%C 10%C This module is part of the \CONTEXT\ macro||package and is 11%C therefore copyrighted by \PRAGMA. See mreadme.pdf for 12%C details. 13 14%D This module is a stripped down version of \type {mult-ini.tex}, which we keep 15%D around as \type {mult-kep.tex} for sentimental reasons. There you will find some 16%D more historic information. 17 18\writestatus{loading}{ConTeXt Multilingual Macros / Initialization} 19 20\unprotect 21 22\pushoverloadmode 23 \registerctxluafile{mult-ini}{autosuffix} 24 \registerctxluafile{mult-fmt}{initexonly} 25\popoverloadmode 26 27%D \macros 28%D [constanten,variabelen,commands] 29%D {v!,c!,k!,s!,e!,m!,l!,r!,f!,p!,x!,y!} 30%D 31%D In the system modules we introduced some prefixed constants, variables (both 32%D macros) and registers. Apart from a tremendous saving in terms of memory and a 33%D gain in speed we use from now on prefixes when possible for just another reason: 34%D consistency and multi||linguality. Systematically using prefixed macros enables 35%D us to implement a multi||lingual user interface. Redefining these next set of 36%D prefixes therefore can have desastrous results. 37%D 38%D \startlinecorrection 39%D \starttable[|c|c|c|] 40%D \HL 41%D \NC \bf prefix \NC \bf meaning \NC \bf application \NC\SR 42%D \HL 43%D \NC \type{\c!prefix!} \NC c! \NC constant (direct) \NC\FR 44%D \NC \type{\k!prefix!} \NC k! \NC constant (indirect) \NC\FR 45%D \NC \type{\e!prefix!} \NC e! \NC element \NC\MR 46%D \NC \type{\f!prefix!} \NC f! \NC file \NC\MR 47%D \NC \type{\m!prefix!} \NC m! \NC age \NC\MR 48%D \NC \type{\s!prefix!} \NC s! \NC system \NC\MR 49%D \NC \type{\v!prefix!} \NC v! \NC variable \NC\MR 50%D \HL 51%D \stoptable 52%D \stoplinecorrection 53%D 54%D In the single||lingual version we used \type {!}, \type {!!}, \type {!!!} and 55%D \type {!!!!}. In the meantime some of these are obsolete (we had some 12 56%D originally). 57 58\immutable\def\c!prefix!{c!} 59\immutable\def\k!prefix!{k!} 60\immutable\def\e!prefix!{e!} 61\immutable\def\f!prefix!{f!} % for the moment we keep this one 62\immutable\def\m!prefix!{m!} 63\immutable\def\s!prefix!{s!} 64\immutable\def\v!prefix!{v!} 65\immutable\def\t!prefix!{t!} 66 67%D \macros 68%D [constants,variables,commands] 69%D {@@,??} 70%D 71%D Variables generated by the system can be recognized on their prefix \type {@@}. 72%D They are composed of a command (class) specific tag, which can be recognized on 73%D \type {??}, and a system constant, which has the prefix \type {c!}. We'll se some 74%D more of this. 75 76\immutable\def\??prefix {??} 77\immutable\def\@@prefix {@@} 78 79%D Just to be complete we repeat some of the already defined system constants here. 80%D Maybe their prefix \type {\s!} now falls into place. 81 82\def\s!next {next} \def\s!default {default} 83\def\s!dummy {dummy} \def\s!unknown {unknown} 84 85\def\s!do {do} \def\s!dodo {dodo} 86 87\def\s!complex {complex} \def\s!start {start} 88\def\s!simple {simple} \def\s!stop {stop} 89 90\def\s!true {true} 91\def\s!false {false} 92 93%D The word \type {height} takes 6~token memory cells. The control sequence \type 94%D {\height} on the other hand uses only one. Knowing this, we can improve the 95%D performance of \TEX, both is terms of speed and memory usage, by using control 96%D sequences instead of the words written in full. 97%D 98%D Where in the \ASCII\ file the second lines takes nine extra characters, \TEX\ 99%D saves us 13~tokens. 100%D 101%D \starttyping 102%D \hrule width 10pt height 2pt depth 1pt 103%D \hrule \s!width 10pt \s!height 2pt \s!depth 1pt 104%D \stoptyping 105%D 106%D One condition is that we have defined \type {\s!height}, \type {\s!width} and 107%D \type {\s!depth} as respectively \type {height}, \type {width} and \type {depth}. 108%D Using this scheme therefore only makes sense when a token sequence is used more 109%D than once. Savings like this should of course be implemented in english, just 110%D because \TEX\ is english. 111 112\def\s!width {width} 113\def\s!height {height} 114\def\s!depth {depth} 115\def\s!spread {spread} 116\def\s!plus {plus} 117\def\s!minus {minus} 118\def\s!to {to} 119 120\def\s!fil {fil} 121\def\s!fill {fill} 122\def\s!filll {filll} 123 124\def\s!attr {attr} 125\def\s!axis {axis} 126\def\s!both {both} 127\def\s!bottom {bottom} 128\def\s!left {left} 129\def\s!options {options} 130\def\s!orientation{orientation} 131\def\s!reverse {reverse} 132\def\s!right {right} 133\def\s!top {top} 134\def\s!xmove {xmove} 135\def\s!xoffset {xoffset} 136\def\s!ymove {ymove} 137\def\s!yoffset {yoffset} 138 139%D \macros 140 141%D {defineinterfaceconstant, 142%D defineinterfacevariable, 143%D defineinterfaceelement, 144%D definesystemvariable, 145%D definesystemconstant, 146%D definemessageconstant, 147%D definefileconstant} 148%D 149%D The first part of this module is dedicated to dealing with multi||lingual 150%D constants and variables. When \CONTEXT\ grew bigger and bigger in terms of bytes 151%D and used string space, we switched to predefined constants. At the cost of more 152%D hash table entries, the macros not only becase more compact, they became much 153%D faster too. Maybe an even bigger advantage was that mispelling could no longer 154%D lead to problems. Even a multi||lingual interface became possible. 155%D 156%D Constants |<|we'll introduce the concept of variables later on|>| are preceded by 157%D a type specific prefix, followed by a \type {!}. To force consistency, we provide 158%D a few commands for defining such constants. 159%D 160%D \starttyping 161%D \defineinterfaceconstant {name} {meaning} 162%D \defineinterfacevariable {name} {meaning} 163%D \defineinterfaceelement {name} {meaning} 164%D \stoptyping 165%D 166%D Which is the same as: 167%D 168%D \starttyping 169%D \def\c!name{meaning} 170%D \def\v!name{meaning} 171%D \def\e!name{meaning} 172%D \stoptyping 173 174%permanent\protected\def\defineinterfaceconstant#1#2{\immutable\defcsname\c!prefix!#1\endcsname{#2}} 175\permanent\protected\def\defineinterfacevariable#1#2{\immutable\defcsname\v!prefix!#1\endcsname{#2}} 176\permanent\protected\def\defineinterfaceelement #1#2{\immutable\defcsname\e!prefix!#1\endcsname{#2}} 177 178%D Next come some interface independant constants: 179%D 180%D \starttyping 181%D \definefileconstant {name} {meaning} 182%D \stoptyping 183 184\permanent\protected\def\definefileconstant#1#2{\immutable\defcsname\f!prefix!#1\endcsname{#2}} 185 186%D And finaly we have the one argument, space saving constants 187%D 188%D \starttyping 189%D \definesystemconstant {name} 190%D \definemessageconstant {name} 191%D \stoptyping 192 193\permanent\protected\def\definesystemconstant #1{\immutable\defcsname\s!prefix!#1\endcsname{#1}} 194\permanent\protected\def\definemessageconstant#1{\immutable\defcsname\m!prefix!#1\endcsname{#1}} 195 196%D For now here: 197 198\permanent\protected\def\definetagconstant #1{\immutable\defcsname\t!prefix!#1\endcsname{#1}} 199\permanent\protected\def\aliastagconstant #1#2{\aliased \letcsname\t!prefix!#1\expandafter\endcsname\csname\t!prefix!#2\endcsname} 200 201%D In a parameter driven system, some parameters are shared by more system 202%D components. In \CONTEXT\ we can distinguish parameters by a unique prefix. Such a 203%D prefix is defined with: 204%D 205%D \starttyping 206%D \definesystemvariable {name} 207%D \stoptyping 208 209\permanent\protected\def\definesystemvariable#1{\immutable\edefcsname\??prefix#1\endcsname{\@@prefix#1}} 210 211\definesystemvariable{ms} 212 213%D \macros 214%D {selectinterface, 215%D defaultinterface, currentinterface, currentresponses} 216%D 217%D With \type {\selectinterface} we specify the language we are going to use. The 218%D system asks for the language wanted, and defaults to \type {\currentinterface} 219%D when we just give \type {enter}. By default the message system uses the current 220%D interface language, but \type {\currentresponses} can specify another language 221%D too. 222%D 223%D Because we want to generate formats directly too, we do not ask for interface 224%D specifications when these are already defined (like in cont-nl.tex and alike). 225 226\ifdefined\defaultinterface 227 228 \permanent\protected\def\selectinterface 229 {\writestatus{interface}{defining \currentinterface\space interface}% 230 %writeline 231 \writestatus{interface}{using \currentresponses\space messages}% 232 %\writeline 233 \enforced\permanent\let\selectinterface\relax} 234 235\else 236 237 \immutable\def\defaultinterface{english} 238 239 \permanent\overloaded\protected\def\selectinterface 240 {\enforced\permanent\protected\def\selectinterface##1##2% 241 {\bgroup 242 \endlinechar\minusone 243 \global\read16 to ##1 244 \egroup 245 \doifnothing\currentinterface{\let##1=##2}% 246 \doifundefined{\s!prefix!##1}{\let##1=##2}}% 247 \selectinterface\currentinterface\defaultinterface 248 \writestatus{interface}{defining \currentinterface\space interface}% 249 %\writeline 250 \selectinterface\currentresponses\currentinterface 251 \writestatus{interface}{using \currentresponses\space messages}% 252 %\writeline 253 \enforced\permanent\let\selectinterface\relax} 254 255\fi 256 257\ifdefined\currentinterface \else \aliased\let\currentinterface\defaultinterface \fi 258\ifdefined\currentresponses \else \aliased\let\currentresponses\defaultinterface \fi 259 260%D \macros 261%D {startinterface} 262%D 263%D Sometimes we want to define things only for specific interface languages. This 264%D can be done by means of the selector: 265%D 266%D \starttyping 267%D \startinterface language 268%D 269%D language specific definitions & commands 270%D 271%D \stopinterface 272%D \stoptyping 273 274\permanent\protected\def\startinterface #1 275 {\doifnot{#1}{all}{\doifnotinset\currentinterface{#1}{\gobbleuntil\stopinterface}}} 276 277\aliased\let\stopinterface\relax 278 279%D \macros 280%D {startmessages, 281%D getmessage, 282%D showmessage, 283%D makemessage} 284%D 285%D A package as large as \CONTEXT\ can hardly function without a decent message 286%D mechanism. Due to its multi||lingual interface, the message subsystem has to be 287%D multi||lingual too. A major drawback of this feature is that we have to code 288%D messages. As a result, the source becomes less self documented. On the other 289%D hand, consistency will improve. 290%D 291%D Because the overhead in terms of entries in the (already exhausted) hash table 292%D has to be minimal, messages are packed in libraries. We can extract a message 293%D from such a library in three ways: 294%D 295%D \starttyping 296%D \getmessage {library} {tag} 297%D \showmessage {library} {tag} {data} 298%D \makemessage {library} {tag} {data} 299%D \stoptyping 300%D 301%D The first command gets the message \type {tag} from the \type {library} 302%D specified. The other commands take an extra argument: a list of items to be 303%D inserted in the message text. While \type {\showmessage} shows the message at the 304%D terminal, the other commands generate the message as text. Before we explain the 305%D \type {data} argument, we give an example of a library. 306%D 307%D \starttyping 308%D \startmessages english library: alfa 309%D title: something 310%D 1: first message 311%D 2: second (--) message -- 312%D \stopmessages 313%D \stoptyping 314%D 315%D The first message is a simple one and can be shown with: 316%D 317%D \starttyping 318%D \showmessage {alfa} {1} {} 319%D \stoptyping 320%D 321%D The second message on the other hand needs some extra data: 322%D 323%D \starttyping 324%D \showmessage {alfa} {2} {and last,to you} 325%D \stoptyping 326%D 327%D This message is shown as: 328%D 329%D \starttyping 330%D something : second (and last) message to you 331%D \stoptyping 332%D 333%D As we can see, the title entry is shown with the message. The data fields are 334%D comma separated and are specified in the message text by \type {--}. 335%D 336%D It is not required to define all messages in a library at once. We can add 337%D messages to a library in the following way: 338%D 339%D \starttyping 340%D \startmessages english library: alfa 341%D 10: tenth message 342%D \stopmessages 343%D \stoptyping 344%D 345%D Because such definitions can take place in different modules, the system gives a 346%D warning when a tag occurs more than once. The first occurrence takes preference 347%D over later ones, so we had better use a save offset, as shown in the example. As 348%D we can see, the title field is specified only the first time! 349%D 350%D Because we want to check for duplicate tags, the macros are a bit more 351%D complicated than neccessary. The \NEWLINE\ token is used as message separator. 352%D 353%D For internal purposes one can use \type {\setmessagetext}, which puts the message 354%D text asked for in \type {\currentmessagetext}. 355%D 356%D These will become obsolete: 357 358\permanent\protected\def\startmessages #1 library: #2 % 359 {\begingroup 360 \ifcsname\m!prefix!#2\endcsname\else\immutable\setgvalue{\m!prefix!#2}{#2}\fi 361 \catcode\endoflineasciicode\othercatcode 362 \doifelseinset{#1}{\currentresponses,all}\mult_messages_start_yes\mult_messages_start_nop{#2}} 363 364\def\mult_messages_start_yes#1#2\stopmessages 365 {{#1}{#2}% 366 \endgroup} 367 368\def\mult_messages_start_nop#1#2\stopmessages 369 {\endgroup} 370 371\aliased\let\stopmessages\relax 372 373\mutable\let\currentmessagetext\empty 374 375\permanent\protected\def\setinterfacemessage#1#2#3% 376 {\ifcsname\m!prefix!#1\endcsname\else\immutable\gdefcsname\m!prefix!#1\endcsname{#1}\fi 377 {#1}{#2}{#3}} 378 379% \getmessage % {tag} {index} -> \currentmessagetext 380% \doifelsemessage % {tag} {index} 381% \showmessage % {tag} {index} {detail} 382% \writestatus % {tag} {string} 383% \message % {string} 384 385\aliased\let\doifmessageelse\doifelsemessage 386 387\permanent\protected\def\inlinemessage #1{\dontleavehmode{\tttf#1}} 388\permanent\protected\def\displaymessage#1{\blank\inlinemessage{#1}\blank} 389 390% \getsetupstring % {tag} defined at the lua end 391% \rawsetupstring % {tag} defined at the lua end 392 393%D For old times sake: 394 395\aliased\let\showwarning\showmessage 396 397%D \macros 398%D {dosetvalue,dosetevalue,dosetgvalue,dosetxvalue,docopyvalue,doresetvalue} % dogetvalue 399%D 400%D We already defined these auxiliary macros in the system modules. Starting with 401%D this module however, we have to take multi||linguality a bit more serious. 402%D 403%D In due time, when we exclusively use the parameter handler code, we can drop the 404%D backmapping (\type{\c!k...}) and make \type {\c!c...} similar to \type {\v!...}. 405%D In that case we can simply the following setters. 406 407\pushoverloadmode 408 409\permanent\protected\def\doletvalue #1#2{\letcsname #1\ifcsname\k!prefix!#2\endcsname\csname\k!prefix!#2\endcsname\else#2\fi\endcsname} 410\permanent\protected\def\dosetvalue #1#2{\defcsname #1\ifcsname\k!prefix!#2\endcsname\csname\k!prefix!#2\endcsname\else#2\fi\endcsname} 411\permanent\protected\def\dosetevalue #1#2{\edefcsname#1\ifcsname\k!prefix!#2\endcsname\csname\k!prefix!#2\endcsname\else#2\fi\endcsname} 412\permanent\protected\def\dosetgvalue #1#2{\gdefcsname#1\ifcsname\k!prefix!#2\endcsname\csname\k!prefix!#2\endcsname\else#2\fi\endcsname} 413\permanent\protected\def\dosetxvalue #1#2{\xdefcsname#1\ifcsname\k!prefix!#2\endcsname\csname\k!prefix!#2\endcsname\else#2\fi\endcsname} 414\permanent\protected\def\doresetvalue #1#2{\letcsname #1\ifcsname\k!prefix!#2\endcsname\csname\k!prefix!#2\endcsname\else#2\fi\endcsname\empty} 415\permanent\protected\def\doignorevalue#1#2#3{\letcsname #1\ifcsname\k!prefix!#2\endcsname\csname\k!prefix!#2\endcsname\else#2\fi\endcsname\empty} 416 417\permanent\protected\def\docopyvalue#1#2#3% 418 {\ifcsname\k!prefix!#3\endcsname 419 \defcsname#1\csname\k!prefix!#3\endcsname\expandafter\endcsname\expandafter 420 {\csname#2\csname\k!prefix!#3\endcsname\endcsname}% 421 \else 422 \defcsname#1#3\expandafter\endcsname\expandafter 423 {\csname#2#3\endcsname}% 424 \fi} 425 426\startinterface english 427 428 \permanent\protected\def\doletvalue #1#2{\letcsname #1#2\endcsname} 429 \permanent\protected\def\dosetvalue #1#2{\defcsname #1#2\endcsname} 430 \permanent\protected\def\dosetevalue #1#2{\edefcsname#1#2\endcsname} 431 \permanent\protected\def\dosetgvalue #1#2{\gdefcsname#1#2\endcsname} 432 \permanent\protected\def\dosetxvalue #1#2{\xdefcsname#1#2\endcsname} 433 \permanent\protected\def\doresetvalue #1#2{\letcsname #1#2\endcsname\empty} 434 \permanent\protected\def\doignorevalue#1#2#3{\letcsname #1#2\endcsname\empty} 435 436 \permanent\protected\def\docopyvalue#1#2#3% 437 {\defcsname#1#3\expandafter\endcsname\expandafter 438 {\csname#2#3\endcsname}} 439 440\stopinterface 441 442\popoverloadmode 443 444%D We can now redefine some messages that will be introduced in the multi||lingual 445%D system module. 446 447\permanent\protected\def\showassignerror #1#2{\showmessage\m!check1{#1,#2}} 448\permanent\protected\def\showargumenterror#1#2{\showmessage\m!check2{#1,#2}} 449\permanent\protected\def\showdefinederror #1#2{\showmessage\m!check3{#1,#2}} 450 451%D \CONTEXT\ is a parameter driven package. This means that users instruct the 452%D system by means of variables, values and keywords. These instructions take the 453%D form: 454%D 455%D \starttyping 456%D \setupsomething[some variable=some value, another one=a keyword] 457%D \stoptyping 458%D 459%D or by keyword only: 460%D 461%D \starttyping 462%D \dosomething[this way,that way,no way] 463%D \stoptyping 464%D 465%D Because the same variables can occur in more than one setup command, we have to 466%D be able to distinguish them. This is achieved by assigning them a unique prefix. 467%D 468%D Imagine a setup command for boxed text, that enables us to specify the height and 469%D width of the box. Behide the scenes the command 470%D 471%D \starttyping 472%D \setupbox [width=12cm, height=3cm] 473%D \stoptyping 474%D 475%D results in something like 476%D 477%D \starttyping 478%D \<box><width> {12cm} 479%D \<box><height> {3cm} 480%D \stoptyping 481%D 482%D while a similar command for specifying the page dimensions 483%D of an \cap {A4} page results in: 484%D 485%D \starttyping 486%D \<page><width> {21.0cm} 487%D \<page><height> {27.9cm} 488%D \stoptyping 489%D 490%D The prefixes \type {<box>} and \type {<page>} are hidden from users and can 491%D therefore be language independant. Variables on the other hand, differ for each 492%D language: 493%D 494%D \starttyping 495%D \<box><color> {<blue>} 496%D \<box><kleur> {<blauw>} 497%D \<box><couleur> {<blue>} 498%D \stoptyping 499%D 500%D In this example we can see that the assigned values or keywords are language 501%D dependant too. This will be a complication when defining multi||lingual setup 502%D files. 503%D 504%D A third phenomena is that variables and values can have a similar meaning. 505%D 506%D \starttyping 507%D \<pagenumber><location> {<left>} 508%D \<skip><left> {12cm} 509%D \stoptyping 510%D 511%D A (minor) complication is that where in english we use \type {<left>}, in dutch 512%D we find both \type {<links>} and \type {<linker>}. This means that when we use 513%D some sort of translation table, we have to distinguish between the variables at 514%D the left side and the fixed values at the right. 515%D 516%D The same goes for commands that are composed of different user supplied and/or 517%D language specific elements. In english we can use: 518%D 519%D \starttyping 520%D \<empty><figure> 521%D \<empty><intermezzo> 522%D \stoptyping 523%D 524%D But in dutch we have the following: 525%D 526%D \starttyping 527%D \<lege><figuur> 528%D \<leeg><intermezzo> 529%D \stoptyping 530%D 531%D These subtle differences automatically lead to a solution where variables, 532%D values, elements and other components have a similar logical name (used in 533%D macro's) but a different meaning (supplied by the user). 534%D 535%D Our solution is one in which the whole system is programmed in terms of 536%D identifiers with language specific meanings. In such an implementation, each 537%D fixed variable is available as: 538%D 539%D \starttyping 540%D \<prefix><variable> 541%D \stoptyping 542%D 543%D This means that for instance: 544%D 545%D \starttyping 546%D \setupbox[width=12cm] 547%D \stoptyping 548%D 549%D expands to something like: 550%D 551%D \starttyping 552%D \def\boxwidth{12cm} 553%D \stoptyping 554%D 555%D because we don't want to recode the source, a setup command in another language 556%D has to expand to this variable, so: 557%D 558%D \starttyping 559%D \setupblock[width=12cm] 560%D \stoptyping 561%D 562%D has to result in the definition of \type {\boxwidth} too. This method enables us 563%D to build compact, fast and readable code. 564%D 565%D An alternative method, which we considered using, uses a more indirect way. In 566%D this case, both calls generate a different variable: 567%D 568%D \starttyping 569%D \def\boxwidth {12cm} 570%D \def\boxbreedte {12cm} 571%D \stoptyping 572%D 573%D And because we don't want to recode those megabytes of already developed code, 574%D this variable has to be called with something like: 575%D 576%D \starttyping 577%D \valueof\box\width 578%D \stoptyping 579%D 580%D where \type {\valueof} takes care of the translation of \type {width} or \type 581%D {breedte} to \type {width} and combining this with \type {box} to \type 582%D {\boxwidth}. 583%D 584%D One advantage of this other scheme is that, within certain limits, we can 585%D implement an interface that can be switched to another language at will, while 586%D the current approach fixes the interface at startup. There are, by the way, other 587%D reasons too for not choosing this scheme. Switching user generated commands is 588%D for instance impossible and a dual interface would therefore give a strange mix 589%D of languages. 590%D 591%D Now let's work out the first scheme. Although the left hand of the assignment is 592%D a variable from the users point of view, it is a constant in terms of the system. 593%D Both \type {width} and \type {breedte} expand to \type {width} because in the 594%D source we only encounter \type {width}. Such system constants are presented as 595%D 596%D \starttyping 597%D \c!width 598%D \stoptyping 599%D 600%D This constant is always equivalent to \type {width}. As we can see, we use \type 601%D {c!} to mark this one as constant. Its dutch counterpart is: 602%D 603%D \starttyping 604%D breedte 605%D \stoptyping 606%D 607%D When we interpret a setup command each variable is translated to it's \type{c!} 608%D counterpart. This means that \type {breedte} and \type{width} expand to \type 609%D {breedte} and \type {\c!width} which both expand to \type {width}. That way user 610%D variables become system constants. 611%D 612%D The interpretation is done by means of a general setup command \type 613%D {\getparameters} that we introduced in the system module. Let us define some 614%D simple setup command: 615%D 616%D \starttyping 617%D \protected\def\setupbox[#1]% 618%D {\getparameters[\??bx][#1]} 619%D \stoptyping 620%D 621%D This command can be used as: 622%D 623%D \starttyping 624%D \setupbox [width=3cm, height=1cm] 625%D \stoptyping 626%D 627%D Afterwards we have two variables \type {\@@bxwidth} and \type {\@@bxheight} which 628%D have the values \type {3cm} and \type {1cm} assigned. These variables are a 629%D combinatiom of the setup prefix \type {\??bx}, which expands to \type {@@bx} and 630%D the translated user supplied variables \type {width} and \type {height} or \type 631%D {breedte} and \type {hoogte}, depending on the actual language. In dutch we just 632%D say: 633%D 634%D \starttyping 635%D \stelblokin [breedte=3cm,hoogte=1cm] 636%D \stoptyping 637%D 638%D and get ourselves \type {\@@bxwidth} and \type {\@@bxheight} too. In the source 639%D of \CONTEXT, we can recognize constants and variables on their leading \type 640%D {c!}, \type {v!} etc., prefixes on \type {??} and composed variables on \type 641%D {@@}. 642%D 643%D We already saw that user supplied keywords need some special treatment too. This 644%D time we don't translate the keyword, but instead use in the source a variable 645%D which meaning depends on the interface language. 646%D 647%D \starttyping 648%D \v!left 649%D \stoptyping 650%D 651%D Which can be used in macro's like: 652%D 653%D \starttyping 654%D \processaction 655%D [\@@bxlocation] 656%D [ \v!left=>\dosomethingontheleft, 657%D \v!middle=>\dosomthinginthemiddle, 658%D \v!right=>\dosomethingontheright] 659%D \stoptyping 660%D 661%D Because variables like \type {\@@bxlocation} can have a lot of meanings, 662%D including tricky expandable tokens, we cannot translate this meaning when we 663%D compare. This means that \type {\@@bxlocation} can be \type {left} of \type 664%D {links} of whatever meaning suits the language. But because \type {\v!left} also 665%D has a meaning that suits the language, we are able to compare. 666%D 667%D Although we know it sounds confusing we want to state two important 668%D characteristics of the interface as described: 669%D 670%D \startnarrower \em 671%D user variables become system constants 672%D \stopnarrower 673%D 674%D and 675%D 676%D \startnarrower \em 677%D user constants (keywords) become system variables 678%D \stopnarrower 679%D 680%D The \type {\c!internal} is a left over from the time that the user interface 681%D documents were not using a specification alongside a keyword specification but 682%D used a shared file in which case we need to go in both directions. 683 684% temporary mkiv hack (we can best just store the whole table in memory) 685 686\permanent\overloaded\protected\def\setinterfaceconstant#1#2% 687 {{#1}{#2}% 688 \immutable\defcsname\c!prefix!#1\endcsname{#1}} 689 690\permanent\overloaded\protected\def\setinterfacevariable#1#2% 691 {{#1}{#2}% 692 \immutable\defcsname\v!prefix!#1\endcsname{#2}} 693 694%D \macros 695%D {defineinterfaceconstant} 696%D 697%D Next we redefine a previously defined macro to take care of interface translation 698%D too. It's a bit redundant, because in these situations we could use the 699%D c||version, but for documentation purposes the x||alternative comes in handy. 700 701\permanent\overloaded\protected\def\defineinterfaceconstant#1#2% 702 {\immutable\defcsname\c!prefix!#1\endcsname{#2}} 703 704%D \macros 705%D {startelements} 706%D 707%D Due to the object oriented nature of \CONTEXT, we also need to define the 708%D elements that are used to build commands. 709%D 710%D Such elements sometimes are the same in different languages, but mostly they 711%D differ. Things can get even confusing when we look at for instance the setup 712%D commands. In english we say \type{\setup<something>}, but in dutch we have: \type 713%D {\stel<iets>in}. Such split elements are no problem, because we just define two 714%D elements. When no second part is needed, we use a \type {-}: 715 716\permanent\overloaded\protected\def\setinterfaceelement#1#2% 717 {{#1}{#2}% 718 \ifcsname\e!prefix!#1\endcsname 719 \doifnotvalue{\e!prefix!#1}{#2}{\enforced\immutable\setvalue{\e!prefix!#1}{#2}}% 720 \else 721 \enforced\immutable\setvalue{\e!prefix!#1}{#2}% 722 \fi} 723 724\permanent\protected\def\setinterfacecommand#1#2% \frozen ? \permanent ? 725 {\doifnot{#1}{#2}% todo: let when already defined 726 {\defcsname#2\expandafter\endcsname\expandafter{\csname#1\endcsname}}} 727 728%D We just ignore these: 729 730\permanent\protected\def\startvariables{\gobbleuntil\stopvariables} \aliased\let\stopvariables\relax 731\permanent\protected\def\startconstants{\gobbleuntil\stopconstants} \aliased\let\stopconstants\relax 732\permanent\protected\def\startelements {\gobbleuntil\stopelements } \aliased\let\stopelements \relax 733\permanent\protected\def\startcommands {\gobbleuntil\stopcommands } \aliased\let\stopcommands \relax 734 735%D For at the \LUA\ end (experiment): 736 737% \def\ui_c#1#2{\immutable\gdefcsname\c!prefix!#1\endcsname{#1}% 738% \immutable\gdefcsname\k!prefix!#2\endcsname{#1}} % backmapping from non english 739% \def\ui_s #1{\immutable\gdefcsname\c!prefix!#1\endcsname{#1}% 740% \immutable\gdefcsname\k!prefix!#1\endcsname{#1}} % backmapping from non english 741% \def\ui_v#1#2{\immutable\gdefcsname\v!prefix!#1\endcsname{#2}} 742% \def\ui_e#1#2{\immutable\gdefcsname\e!prefix!#1\endcsname{#2}} 743% \def\ui_a#1#2{\frozen\protected\def#2{#1}} % will go away 744% 745% \startinterface english 746% 747% \def\ui_c#1#2{\immutable\gdefcsname\c!prefix!#1\endcsname{#1}} 748% \def\ui_s #1{\immutable\gdefcsname\c!prefix!#1\endcsname{#1}} 749% 750% \stopinterface 751 752%D So much for the basic multi||lingual interface commands. The macro's can be 753%D enhanced with more testing facilities, but for the moment they suffice. 754 755% use \Uchar 756 757\ifdefined\zwnj \else \immutable\edef\zwnj{utf.char(\number"200C)}} \fi % needed for cont-pe % maybe to char-utf.mkiv 758\ifdefined\zwj \else \immutable\edef\zwj {\directlua{utf.char(\number"200D)} \fi % needed for cont-pe % maybe to char-utf.mkiv 759 760%D \macros 761%D {contextversion, contextversionnumber, contextversionno, 762%D contextbanner, showcontextbanner, formatversion} 763%D 764%D Out of convenience we define the banners here. This might move to the \LUA\ end. 765 766\pushoverloadmode 767 768\permanent\overloaded\def\contextbanner 769 {ConTeXt \space 770 ver: \contextversion \space \contextmark \space \space 771 fmt: \formatversion \space \space 772 int: \currentinterface/\currentresponses} 773 774\permanent\overloaded\protected\def\showcontextbanner 775 {\writestatus\m!system\empty 776 \writestatus\m!system\contextbanner 777 \writestatus\m!system\empty} 778 779\immutable\overloaded\edef\formatversion 780 {\the\normalyear.\the\normalmonth.\the\normalday} 781 782\newcount\contextversionno 783 784\ifdefined\contextversion \else 785 \immutable\edef\contextversion{\the\normalyear.\the\normalmonth.\the\normalday\space 00:00} 786\fi 787 788\permanent\overloaded\protected\def \contextversionnumber #1.#2.#3 #4:#5\relax{#1#2#3} 789 \contextversionno \expandafter\contextversionnumber\contextversion\relax 790\immutable\overloaded \edef\contextversionnumber {\the\contextversionno\space\contextmark} 791 792\popoverloadmode 793 794%D \macros 795%D {everydump} 796%D 797%D This one is only used when we generate the format. 798 799% \ifdefined\everydump \else 800% \newtoks\everydump 801% \def\dump{\the\everydump\global\everydump\emptytoks\glet\dump\relax\normaldump} 802% \fi 803 804% \appendtoks \showcontextbanner \to \everydump 805 806\protect \endinput 807 |