1Locale::Po4a::TransTractor(3pm) Po4a Tools Locale::Po4a::TransTractor(3pm)
2
6 Locale::Po4a::TransTractor - generic trans(lator ex)tractor.
7
9 The po4a (PO for anything) project goal is to ease translations (and
10 more interestingly, the maintenance of translations) using gettext
11 tools on areas where they were not expected like documentation.
12 This class is the ancestor of every po4a parser used to parse a
14 document, to search translatable strings, to extract them to a PO file
15 and to replace them by their translation in the output document.
16 More formally, it takes the following arguments as input:
18 - a document to translate;
20 - a PO file containing the translations to use.
22 As output, it produces:
24 - another PO file, resulting of the extraction of translatable strings
26 from the input document;
27 - a translated document, with the same structure than the one in input,
29 but with all translatable strings replaced with the translations
30 found in the PO file provided in input.
31 Here is a graphical representation of this:
33 Input document --\ /---> Output document
35 \ / (translated)
36 +-> parse() function -----+
37 / \
38 Input PO --------/ \---> Output PO
39 (extracted)
40
42 parse()
43 This is where all the work takes place: the parsing of input
44 documents, the generation of output, and the extraction of the
45 translatable strings. This is pretty simple using the provided
46 functions presented in the section INTERNAL FUNCTIONS below. See
47 also the SYNOPSIS, which presents an example.
48 This function is called by the process() function below, but if you
50 choose to use the new() function, and to add content manually to
51 your document, you will have to call this function yourself.
52 docheader()
54 This function returns the header we should add to the produced
55 document, quoted properly to be a comment in the target language.
56 See the section Educating developers about translations, from
57 po4a(7), for what it is good for.
58
60 The following example parses a list of paragraphs beginning with "<p>".
61 For the sake of simplicity, we assume that the document is well
62 formatted, i.e. that '<p>' tags are the only tags present, and that
63 this tag is at the very beginning of each paragraph.
64 sub parse {
66 my $self = shift;
67 PARAGRAPH: while (1) {
69 my ($paragraph,$pararef)=("","");
70 my $first=1;
71 my ($line,$lref)=$self->shiftline();
72 while (defined($line)) {
73 if ($line =~ m/<p>/ && !$first--; ) {
74 # Not the first time we see <p>.
75 # Reput the current line in input,
76 # and put the built paragraph to output
77 $self->unshiftline($line,$lref);
78 # Now that the document is formed, translate it:
80 # - Remove the leading tag
81 $paragraph =~ s/^<p>//s;
82 # - push to output the leading tag (untranslated) and the
84 # rest of the paragraph (translated)
85 $self->pushline( "<p>"
86 . $document->translate($paragraph,$pararef)
87 );
88 next PARAGRAPH;
90 } else {
91 # Append to the paragraph
92 $paragraph .= $line;
93 $pararef = $lref unless(length($pararef));
94 }
95 # Reinit the loop
97 ($line,$lref)=$self->shiftline();
98 }
99 # Did not get a defined line? End of input file.
100 return;
101 }
102 }
103 Once you've implemented the parse function, you can use your document
105 class, using the public interface presented in the next section.
106
108 Constructor
109 process(%)
110 This function can do all you need to do with a po4a document in one
111 invocation. Its arguments must be packed as a hash. ACTIONS:
112 a. Reads all the PO files specified in po_in_name
114 b. Reads all original documents specified in file_in_name
116 c. Parses the document
118 d. Reads and applies all the addenda specified
120 e. Writes the translated document to file_out_name (if given)
122 f. Writes the extracted PO file to po_out_name (if given)
124 ARGUMENTS, beside the ones accepted by new() (with expected type):
126 file_in_name (@)
128 List of filenames where we should read the input document.
129 file_in_charset ($)
131 Charset used in the input document (if it isn't specified, it
132 will try to detect it from the input document).
133 file_out_name ($)
135 Filename where we should write the output document.
136 file_out_charset ($)
138 Charset used in the output document (if it isn't specified, it
139 will use the PO file charset).
140 po_in_name (@)
142 List of filenames where we should read the input PO files from,
143 containing the translation which will be used to translate the
144 document.
145 po_out_name ($)
147 Filename where we should write the output PO file, containing
148 the strings extracted from the input document.
149 addendum (@)
151 List of filenames where we should read the addenda from.
152 addendum_charset ($)
154 Charset for the addenda.
155 new(%)
157 Create a new po4a document. Accepted options (but be in a hash):
158 verbose ($)
160 Sets the verbosity.
161 debug ($)
163 Sets the debugging.
164 Manipulating document files
166 read($)
167 Add another input document at the end of the existing one. The
168 argument is the filename to read.
169 Please note that it does not parse anything. You should use the
171 parse() function when you're done with packing input files into the
172 document.
173 write($)
175 Write the translated document to the given filename.
176 Manipulating PO files
178 readpo($)
179 Add the content of a file (which name is passed as argument) to the
180 existing input PO. The old content is not discarded.
181 writepo($)
183 Write the extracted PO file to the given filename.
184 stats()
186 Returns some statistics about the translation done so far. Please
187 note that it's not the same statistics than the one printed by
188 msgfmt --statistic. Here, it's stats about recent usage of the PO
189 file, while msgfmt reports the status of the file. It is a wrapper
190 to the Locale::Po4a::Po::stats_get function applied to the input PO
191 file. Example of use:
192 [normal use of the po4a document...]
194 ($percent,$hit,$queries) = $document->stats();
196 print "We found translations for $percent\% ($hit from $queries) of strings.\n";
197 is_po_uptodate()
199 Returns ($uptodate, $diagnostic) where $uptodate is whether the
200 input po and the output po match (if not, it means that the input
201 po should be updated) and $diagnostic is a string explaining why
202 the po file is not uptodate, when this happens.
203 Manipulating addenda
205 addendum($)
206 Please refer to po4a(7) for more information on what addenda are,
207 and how translators should write them. To apply an addendum to the
208 translated document, simply pass its filename to this function and
209 you are done ;)
210 This function returns a non-null integer on error.
212
214 Getting input, providing output
215 Four functions are provided to get input and return output. They are
216 very similar to shift/unshift and push/pop. The first pair is about
217 input, while the second is about output. Mnemonic: in input, you are
218 interested in the first line, what shift gives, and in output you want
219 to add your result at the end, like push does.
220 shiftline()
222 This function returns the next line of the doc_in to be parsed and
223 its reference (packed as an array).
224 unshiftline($$)
226 Unshifts a line of the input document and its reference.
227 pushline($)
229 Push a new line to the doc_out.
230 popline()
232 Pop the last pushed line from the doc_out.
233 Marking strings as translatable
235 One function is provided to handle the text which should be translated.
236 translate($$$)
238 Mandatory arguments:
239 - A string to translate
241 - The reference of this string (i.e. position in inputfile)
243 - The type of this string (i.e. the textual description of its
245 structural role; used in Locale::Po4a::Po::gettextization(); see
246 also po4a(7), section Gettextization: how does it work?)
247 This function can also take some extra arguments. They must be
249 organized as a hash. For example:
250 $self->translate("string","ref","type",
252 'wrap' => 1);
253 wrap
255 boolean indicating whether we can consider that whitespaces in
256 string are not important. If yes, the function canonizes the
257 string before looking for a translation or extracting it, and
258 wraps the translation.
259 wrapcol
261 the column at which we should wrap (default: 76).
262 comment
264 an extra comment to add to the entry.
265 Actions:
267 - Pushes the string, reference and type to po_out.
269 - Returns the translation of the string (as found in po_in) so that
271 the parser can build the doc_out.
272 - Handles the charsets to recode the strings before sending them to
274 po_out and before returning the translations.
275 Misc functions
277 verbose()
278 Returns if the verbose option was passed during the creation of the
279 TransTractor.
280 debug()
282 Returns if the debug option was passed during the creation of the
283 TransTractor.
284 detected_charset($)
286 This tells TransTractor that a new charset (the first argument) has
287 been detected from the input document. It can usually be read from
288 the document header. Only the first charset will remain, coming
289 either from the process() arguments or detected from the document.
290 get_out_charset()
292 This function will return the charset that should be used in the
293 output document (usually useful to substitute the input document's
294 detected charset where it has been found).
295 It will use the output charset specified in the command line. If it
297 wasn't specified, it will use the input PO's charset, and if the
298 input PO has the default "CHARSET", it will return the input
299 document's charset, so that no encoding is performed.
300 recode_skipped_text($)
302 This function returns the recoded text passed as argument, from the
303 input document's charset to the output document's one. This isn't
304 needed when translating a string (translate() recodes everything
305 itself), but it is when you skip a string from the input document
306 and you want the output document to be consistent with the global
307 encoding.
308
310 One shortcoming of the current TransTractor is that it can't handle
311 translated document containing all languages, like debconf templates,
312 or .desktop files.
313 To address this problem, the only interface changes needed are:
315 - take a hash as po_in_name (a list per language)
317 - add an argument to translate to indicate the target language
319 - make a pushline_all function, which would make pushline of its
321 content for all languages, using a map-like syntax:
322 $self->pushline_all({ "Description[".$langcode."]=".
324 $self->translate($line,$ref,$langcode)
325 });
326 Will see if it's enough ;)
328
330 Denis Barbier <barbier@linuxfr.org>
331 Martin Quinson (mquinson#debian.org)
332 Jordi Vilalta <jvprat@gmail.com>
333Po4a Tools 2019-02-02 Locale::Po4a::TransTractor(3pm)