1docstrip_util(n) Literate programming tool docstrip_util(n)
2______________________________________________________________________________
6
8 docstrip_util - Docstrip-related utilities
9
11 package require Tcl 8.4
12 package require docstrip ?1.2?
14 package require docstrip::util ?1.3.1?
16 pkgProvide name version terminals
18 pkgIndex ?terminal ...?
20 fileoptions ?option value ...?
22 docstrip::util::index_from_catalogue dir pattern ?option value ...?
24 docstrip::util::modules_from_catalogue target source ?option value ...?
26 docstrip::util::classical_preamble metaprefix message target ?source
28 terminals ...?
29 docstrip::util::classical_postamble metaprefix message target ?source
31 terminals ...?
32 docstrip::util::packages_provided text ?setup-script?
34 docstrip::util::ddt2man text
36 docstrip::util::guards subcmd text
38 docstrip::util::patch source-var terminals fromtext diff ?option value
40 ...?
41 docstrip::util::thefile filename ?option value ...?
43 docstrip::util::import_unidiff diff-text ?warning-var?
45______________________________________________________________________________
47
49 The docstrip::util package is meant for collecting various utility pro‐
50 cedures that are mainly useful at installation or development time. It
51 is separate from the base package to avoid overhead when the latter is
52 used to source code.
53
55 Like raw ".tcl" files, code lines in docstrip source files can be
56 searched for package declarations and corresponding indices con‐
57 structed. A complication is however that one cannot tell from the code
58 blocks themselves which will fit together to make a working package;
59 normally that information would be found in an accompanying ".ins"
60 file, but parsing one of those is not an easy task. Therefore doc‐
61 strip::util introduces an alternative encoding of such information, in
62 the form of a declarative Tcl script: the catalogue (of the contents in
63 a source file).
64 The special commands which are available inside a catalogue are:
66 pkgProvide name version terminals
68 Declares that the code for a package with name name and version
69 version is made up from those modules in the source file which
70 are selected by the terminals list of guard expression termi‐
71 nals. This code should preferably not contain a package provide
72 command for the package, as one will be provided by the package
73 loading mechanisms.
74 pkgIndex ?terminal ...?
76 Declares that the code for a package is made up from those mod‐
77 ules in the source file which are selected by the listed guard
78 expression terminals. The name and version of this package is
79 determined from package provide command(s) found in that code
80 (hence there must be such a command in there).
81 fileoptions ?option value ...?
83 Declares the fconfigure options that should be in force when
84 reading the source; this can usually be ignored for pure ASCII
85 files, but if the file needs to be interpreted according to some
86 other -encoding then this is how to specify it. The command
87 should normally appear first in the catalogue, as it takes
88 effect only for commands following it.
89 Other Tcl commands are supported too — a catalogue is parsed by being
91 evaluated in a safe interpreter — but they are rarely needed. To allow
92 for future extensions, unknown commands in the catalogue are silently
93 ignored.
94 To simplify distribution of catalogues together with their source
96 files, the catalogue is stored in the source file itself as a module
97 selected by the terminal 'docstrip.tcl::catalogue'. This supports both
98 the style of collecting all catalogue lines in one place and the style
99 of putting each catalogue line in close proximity of the code that it
100 declares.
101 Putting catalogue entries next to the code they declare may look as
103 follows
104 % First there's the catalogue entry
107 % \begin{tcl}
108 %<docstrip.tcl::catalogue>pkgProvide foo::bar 1.0 {foobar load}
109 % \end{tcl}
110 % second a metacomment used to include a copyright message
111 % \begin{macrocode}
112 %<*foobar>
113 %% This file is placed in the public domain.
114 % \end{macrocode}
115 % third the package implementation
116 % \begin{tcl}
117 namespace eval foo::bar {
118 # ... some clever piece of Tcl code elided ...
119 % \end{tcl}
120 % which at some point may have variant code to make use of a
121 % |load|able extension
122 % \begin{tcl}
123 %<*load>
124 load [file rootname [info script]][info sharedlibextension]
125 %</load>
126 %<*!load>
127 # ... even more clever scripted counterpart of the extension
128 # also elided ...
129 %</!load>
130 }
131 %</foobar>
132 % \end{tcl}
133 % and that's it!
134 The corresponding set-up with pkgIndex would be
136 % First there's the catalogue entry
139 % \begin{tcl}
140 %<docstrip.tcl::catalogue>pkgIndex foobar load
141 % \end{tcl}
142 % second a metacomment used to include a copyright message
143 % \begin{tcl}
144 %<*foobar>
145 %% This file is placed in the public domain.
146 % \end{tcl}
147 % third the package implementation
148 % \begin{tcl}
149 package provide foo::bar 1.0
150 namespace eval foo::bar {
151 # ... some clever piece of Tcl code elided ...
152 % \end{tcl}
153 % which at some point may have variant code to make use of a
154 % |load|able extension
155 % \begin{tcl}
156 %<*load>
157 load [file rootname [info script]][info sharedlibextension]
158 %</load>
159 %<*!load>
160 # ... even more clever scripted counterpart of the extension
161 # also elided ...
162 %</!load>
163 }
164 %</foobar>
165 % \end{tcl}
166 % and that's it!
167 docstrip::util::index_from_catalogue dir pattern ?option value ...?
170 This command is a sibling of the standard pkg_mkIndex command,
171 in that it adds package entries to "pkgIndex.tcl" files. The
172 difference is that it indexes docstrip-style source files rather
173 than raw ".tcl" or loadable library files. Only packages listed
174 in the catalogue of a file are considered.
175 The dir argument is the directory in which to look for files
177 (and whose "pkgIndex.tcl" file should be amended). The pattern
178 argument is a glob pattern of files to look into; a typical
179 value would be *.dtx or *.{dtx,ddt}. Remaining arguments are
180 option-value pairs, where the supported options are:
181 -recursein dirpattern
183 If this option is given, then the index_from_catalogue
184 operation will be repeated in each subdirectory whose
185 name matches the dirpattern. -recursein * will cause the
186 entire subtree rooted at dir to be indexed.
187 -sourceconf dictionary
189 Specify fileoptions to use when reading the catalogues of
190 files (and also for reading the packages if the catalogue
191 does not contain a fileoptions command). Defaults to
192 being empty. Primarily useful if your system encoding is
193 very different from that of the source file (e.g., one is
194 a two-byte encoding and the other is a one-byte encod‐
195 ing). ascii and utf-8 are not very different in that
196 sense.
197 -options terminals
199 The terminals is a list of terminals in addition to doc‐
200 strip.tcl::catalogue that should be held as true when
201 extracting the catalogue. Defaults to being empty. This
202 makes it possible to make use of "variant sections" in
203 the catalogue itself, e.g. gaurd some entries with an
204 extra "experimental" and thus prevent them from appearing
205 in the index unless that is generated with "experimental"
206 among the -options.
207 -report boolean
209 If the boolean is true then the return value will be a
210 textual, probably multiline, report on what was done.
211 Defaults to false, in which case there is no particular
212 return value.
213 -reportcmd commandPrefix
215 Every item in the report is handed as an extra argument
216 to the command prefix. Since index_from_catalogue would
217 typically be used at a rather high level in installation
218 scripts and the like, the commandPrefix defaults to "puts
219 stdout". Use list to effectively disable this feature.
220 The return values from the prefix are ignored.
221 The package ifneeded scripts that are generated contain one
223 package require docstrip command and one docstrip::sourcefrom
224 command. If the catalogue entry was of the pkgProvide kind then
225 the package ifneeded script also contains the package provide
226 command.
227 Note that index_from_catalogue never removes anything from an
229 existing "pkgIndex.tcl" file. Hence you may need to delete it
230 (or have pkg_mkIndex recreate it from scratch) before running
231 index_from_catalogue to update some piece of information, such
232 as a package version number.
233 docstrip::util::modules_from_catalogue target source ?option value ...?
236 This command is an alternative to index_from_catalogue which
237 creates Tcl Module (".tm") files rather than "pkgIndex.tcl"
238 entries. Since this action is more similar to what docstrip
239 classically does, it has features for putting pre- and postam‐
240 bles on the generated files.
241 The source argument is the name of the source file to generate
243 ".tm" files from. The target argument is the directory which
244 should count as a module path, i.e., this is what the relative
245 paths derived from package names are joined to. The supported
246 options are:
247 -preamble message
249 A message to put in the preamble (initial block of com‐
250 ments) of generated files. Defaults to a space. May be
251 several lines, which are then separated by newlines. Tra‐
252 ditionally used for copyright notices or the like, but
253 metacomment lines provide an alternative to that.
254 -postamble message
256 Like -preamble, but the message is put at the end of the
257 file instead of the beginning. Defaults to being empty.
258 -sourceconf dictionary
260 Specify fileoptions to use when reading the catalogue of
261 the source (and also for reading the packages if the cat‐
262 alogue does not contain a fileoptions command). Defaults
263 to being empty. Primarily useful if your system encoding
264 is very different from that of the source file (e.g., one
265 is a two-byte encoding and the other is a one-byte encod‐
266 ing). ascii and utf-8 are not very different in that
267 sense.
268 -options terminals
270 The terminals is a list of terminals in addition to doc‐
271 strip.tcl::catalogue that should be held as true when
272 extracting the catalogue. Defaults to being empty. This
273 makes it possible to make use of "variant sections" in
274 the catalogue itself, e.g. gaurd some entries with an
275 extra "experimental" guard and thus prevent them from
276 contributing packages unless those are generated with
277 "experimental" among the -options.
278 -formatpreamble commandPrefix
280 Command prefix used to actually format the preamble.
281 Takes four additional arguments message, targetFilename,
282 sourceFilename, and terminalList and returns a fully for‐
283 matted preamble. Defaults to using classical_preamble
284 with a metaprefix of '##'.
285 -formatpostamble commandPrefix
287 Command prefix used to actually format the postamble.
288 Takes four additional arguments message, targetFilename,
289 sourceFilename, and terminalList and returns a fully for‐
290 matted postamble. Defaults to using classical_postamble
291 with a metaprefix of '##'.
292 -report boolean
294 If the boolean is true (which is the default) then the
295 return value will be a textual, probably multiline,
296 report on what was done. If it is false then there is no
297 particular return value.
298 -reportcmd commandPrefix
300 Every item in the report is handed as an extra argument
301 to this command prefix. Defaults to list, which effec‐
302 tively disables this feature. The return values from the
303 prefix are ignored. Use for example "puts stdout" to get
304 report items written immediately to the terminal.
305 An existing file of the same name as one to be created will be
307 overwritten.
308 docstrip::util::classical_preamble metaprefix message target ?source
310 terminals ...?
311 This command returns a preamble in the classical docstrip style
312 ##
315 ## This is `TARGET',
316 ## generated by the docstrip::util package.
317 ##
318 ## The original source files were:
319 ##
320 ## SOURCE (with options: `foo,bar')
321 ##
322 ## Some message line 1
323 ## line2
324 ## line3
325 if called as
328 docstrip::util::classical_preamble {##}\
331 "\nSome message line 1\nline2\nline3" TARGET SOURCE {foo bar}
332 The command supports preambles for files generated from multiple
335 sources, even though modules_from_catalogue at present does not
336 need that.
337 docstrip::util::classical_postamble metaprefix message target ?source
339 terminals ...?
340 This command returns a postamble in the classical docstrip style
341 ## Some message line 1
344 ## line2
345 ## line3
346 ##
347 ## End of file `TARGET'.
348 if called as
351 docstrip::util::classical_postamble {##}\
354 "Some message line 1\nline2\nline3" TARGET SOURCE {foo bar}
355 In other words, the source and terminals arguments are ignored,
358 but supported for symmetry with classical_preamble.
359 docstrip::util::packages_provided text ?setup-script?
361 This command returns a list where every even index element is
362 the name of a package provided by text when that is evaluated as
363 a Tcl script, and the following odd index element is the corre‐
364 sponding version. It is used to do package indexing of extracted
365 pieces of code, in the manner of pkg_mkIndex.
366 One difference to pkg_mkIndex is that the text gets evaluated in
368 a safe interpreter. package require commands are silently
369 ignored, as are unknown commands (which includes source and
370 load). Other errors cause processing of the text to stop, in
371 which case only those package declarations that had been encoun‐
372 tered before the error will be included in the return value.
373 The setup-script argument can be used to customise the evalua‐
375 tion environment, if the code in text has some very special
376 needs. The setup-script is evaluated in the local context of the
377 packages_provided procedure just before the text is processed.
378 At that time, the name of the slave command for the safe inter‐
379 preter that will do this processing is kept in the local vari‐
380 able c. To for example copy the contents of the ::env array to
381 the safe interpreter, one might use a setup-script of
382 $c eval [list array set env [array get ::env]]
384
386 Unlike the previous group of commands, which would use doc‐
387 strip::extract to extract some code lines and then process those fur‐
388 ther, the following commands operate on text consisting of all types of
389 lines.
390 docstrip::util::ddt2man text
392 The ddt2man command reformats text from the general docstrip
393 format to doctools ".man" format (Tcl Markup Language for Man‐
394 pages). The different line types are treated as follows:
395 comment and metacomment lines
397 The '%' and '%%' prefixes are removed, the rest of the
398 text is kept as it is.
399 empty lines
401 These are kept as they are. (Effectively this means that
402 they will count as comment lines after a comment line and
403 as code lines after a code line.)
404 code lines
406 example_begin and example_end commands are placed at the
407 beginning and end of every block of consecutive code
408 lines. Brackets in a code line are converted to lb and rb
409 commands.
410 verbatim guards
412 These are processed as usual, so they do not show up in
413 the result but every line in a verbatim block is treated
414 as a code line.
415 other guards
417 These are treated as code lines, except that the actual
418 guard is emphasised.
419 At the time of writing, no project has employed doctools markup
421 in master source files, so experience of what works well is not
422 available. A source file could however look as follows
423 % [manpage_begin gcd n 1.0]
426 % [keywords divisor]
427 % [keywords math]
428 % [moddesc {Greatest Common Divisor}]
429 % [require gcd [opt 1.0]]
430 % [description]
431 %
432 % [list_begin definitions]
433 % [call [cmd gcd] [arg a] [arg b]]
434 % The [cmd gcd] procedure takes two arguments [arg a] and [arg b] which
435 % must be integers and returns their greatest common divisor.
436 proc gcd {a b} {
437 % The first step is to take the absolute values of the arguments.
438 % This relieves us of having to worry about how signs will be treated
439 % by the remainder operation.
440 set a [expr {abs($a)}]
441 set b [expr {abs($b)}]
442 % The next line does all of Euclid's algorithm! We can make do
443 % without a temporary variable, since $a is substituted before the
444 % [lb]set a $b[rb] and thus continues to hold a reference to the
445 % "old" value of [var a].
446 while {$b>0} { set b [expr { $a % [set a $b] }] }
447 % In Tcl 8.3 we might want to use [cmd set] instead of [cmd return]
448 % to get the slight advantage of byte-compilation.
449 %<tcl83> set a
450 %<!tcl83> return $a
451 }
452 % [list_end]
453 %
454 % [manpage_end]
455 If the above text is fed through docstrip::util::ddt2man then
458 the result will be a syntactically correct doctools manpage,
459 even though its purpose is a bit different.
460 It is suggested that master source code files with doctools
462 markup are given the suffix ".ddt", hence the "ddt" in ddt2man.
463 docstrip::util::guards subcmd text
465 The guards command returns information (mostly of a statistical
466 nature) about the ordinary docstrip guards that occur in the
467 text. The subcmd selects what is returned.
468 counts List the guard expression terminals with counts. The for‐
470 mat of the return value is a dictionary which maps the
471 terminal name to the number of occurencies of it in the
472 file.
473 exprcount
475 List the guard expressions with counts. The format of the
476 return value is a dictionary which maps the expression to
477 the number of occurencies of it in the file.
478 exprerr
480 List the syntactically incorrect guard expressions (e.g.
481 parentheses do not match, or a terminal is missing). The
482 return value is a list, with the elements in no particu‐
483 lar order.
484 expressions
486 List the guard expressions. The return value is a list,
487 with the elements in no particular order.
488 exprmods
490 List the guard expressions with modifiers. The format of
491 the return value is a dictionary where each index is a
492 guard expression and each entry is a string with one
493 character for every guard line that has this expression.
494 The characters in the entry specify what modifier was
495 used in that line: +, -, *, /, or (for guard without mod‐
496 ifier:) space. This is the most primitive form of the
497 information gathered by guards.
498 names List the guard expression terminals. The return value is
500 a list, with the elements in no particular order.
501 rotten List the malformed guard lines (this does not include
503 lines where only the expression is malformed, though).
504 The format of the return value is a dictionary which maps
505 line numbers to their contents.
506 docstrip::util::patch source-var terminals fromtext diff ?option value
508 ...?
509 This command tries to apply a diff file (for example a contrib‐
510 uted patch) that was computed for a generated file to the doc‐
511 strip source. This can be useful if someone has edited a gener‐
512 ated file, thus mistaking it for being the source. This command
513 makes no presumptions which are specific for the case that the
514 generated file is a Tcl script.
515 patch requires that the source file to patch is kept as a list
517 of lines in a variable, and the name of that variable in the
518 calling context is what goes into the source-var argument. The
519 terminals is the list of terminals used to extract the file that
520 has been patched. The diff is the actual diff to apply (in a
521 format as explained below) and the fromtext is the contents of
522 the file which served as "from" when the diff was computed.
523 Options can be used to further control the process.
524 The process works by "lifting" the hunks in the diff from gener‐
526 ated to source file, and then applying them to the elements of
527 the source-var. In order to do this lifting, it is necessary to
528 determine how lines in the fromtext correspond to elements of
529 the source-var, and that is where the terminals come in; the
530 source is first extracted under the given terminals, and the
531 result of that is then matched against the fromtext. This pro‐
532 duces a map which translates line numbers stated in the diff to
533 element numbers in source-var, which is what is needed to lift
534 the hunks.
535 The reason that both the terminals and the fromtext must be
537 given is twofold. First, it is very difficult to keep track of
538 how many lines of preamble are supplied some other way than by
539 copying lines from source files. Second, a generated file might
540 contain material from several source files. Both make it impos‐
541 sible to predict what line number an extracted file would have
542 in the generated file, so instead the algorithm for computing
543 the line number map looks for a block of lines in the fromtext
544 which matches what can be extracted from the source. This match‐
545 ing is affected by the following options:
546 -matching mode
548 How equal must two lines be in order to match? The sup‐
549 ported modes are:
550 exact Lines must be equal as strings. This is the
552 default.
553 anyspace
555 All sequences of whitespace characters are con‐
556 verted to single spaces before comparing.
557 nonspace
559 Only non-whitespace characters are considered when
560 comparing.
561 none Any two lines are considered to be equal.
563 -metaprefix string
565 The -metaprefix value to use when extracting. Defaults to
566 "%%", but for Tcl code it is more likely that "#" or "##"
567 had been used for the generated file.
568 -trimlines boolean
570 The -trimlines value to use when extracting. Defaults to
571 true.
572 The return value is in the form of a unified diff, containing
574 only those hunks which were not applied or were only partially
575 applied; a comment in the header of each hunk specifies which
576 case is at hand. It is normally necessary to manually review
577 both the return value from patch and the patched text itself, as
578 this command cannot adjust comment lines to match new content.
579 An example use would look like
581 set sourceL [split [docstrip::util::thefile from.dtx] \n]
584 set terminals {foo bar baz}
585 set fromtext [docstrip::util::thefile from.tcl]
586 set difftext [exec diff --unified from.tcl to.tcl]
587 set leftover [docstrip::util::patch sourceL $terminals $fromtext\
588 [docstrip::util::import_unidiff $difftext] -metaprefix {#}]
589 set F [open to.dtx w]; puts $F [join $sourceL \n]; close $F
590 return $leftover
591 Here, "from.dtx" was used as source for "from.tcl", which some‐
594 one modified into "to.tcl". We're trying to construct a "to.dtx"
595 which can be used as source for "to.tcl".
596 docstrip::util::thefile filename ?option value ...?
598 The thefile command opens the file filename, reads it to end,
599 closes it, and returns the contents (dropping a final newline if
600 there is one). The option-value pairs are passed on to fconfig‐
601 ure to configure the open file channel before anything is read
602 from it.
603 docstrip::util::import_unidiff diff-text ?warning-var?
605 This command parses a unified (diff flags -U and --unified) for‐
606 mat diff into the list-of-hunks format expected by doc‐
607 strip::util::patch. The diff-text argument is the text to parse
608 and the warning-var is, if specified, the name in the calling
609 context of a variable to which any warnings about parsing prob‐
610 lems will be appended.
611 The return value is a list of hunks. Each hunk is a list of five
613 elements "start1 end1 start2 end2 lines". start1 and end1 are
614 line numbers in the "from" file of the first and last respec‐
615 tively lines of the hunk. start2 and end2 are the corresponding
616 line numbers in the "to" file. Line numbers start at 1. The
617 lines is a list with two elements for each line in the hunk; the
618 first specifies the type of a line and the second is the actual
619 line contents. The type is - for lines only in the "from" file,
620 + for lines that are only in the "to" file, and 0 for lines that
621 are in both.
622
624 docstrip, doctools, doctools_fmt
625
627 \.ddt, .dtx, LaTeX, Tcl module, catalogue, diff, docstrip, doctools,
628 documentation, literate programming, module, package indexing, patch,
629 source
630
632 Documentation tools
633
635 Copyright (c) 2003–2010 Lars Hellström <Lars dot Hellstrom at residenset dot net>
636tcllib 1.3.1 docstrip_util(n)