Section: User Contributed Perl Documentation (3)Updated: 2010-11-30Local indexUp
NAME
Locale::Po4a::Po - PO file manipulation module
SYNOPSIS
use Locale::Po4a::Po;
my $pofile=Locale::Po4a::Po->new();
# Read PO file
$pofile->read('file.po');
# Add an entry
$pofile->push('msgid' => 'Hello', 'msgstr' => 'bonjour',
'flags' => "wrap", 'reference'=>'file.c:46');
# Extract a translation
$pofile->gettext("Hello"); # returns 'bonjour'
# Write back to a file
$pofile->write('otherfile.po');
DESCRIPTION
Locale::Po4a::Po is a module that allows you to manipulate message
catalogs. You can load and write from/to a file (which extension is often
po), you can build new entries on the fly or request for the translation
of a string.
For a more complete description of message catalogs in the PO format and
their use, please refer to the documentation of the gettext program.
This module is part of the PO4A project, which objective is to use PO files
(designed at origin to ease the translation of program messages) to
translate everything, including documentation (man page, info manual),
package description, debconf templates, and everything which may benefit
from this.
OPTIONS ACCEPTED BY THIS MODULE
porefs
This specifies the reference format. It can be one of none to not produce
any reference, noline to not specify the line number, and full to
include complete references.
Functions about whole message catalogs
new()
Creates a new message catalog. If an argument is provided, it's the name of
a PO file we should load.
read($)
Reads a PO file (which name is given as argument). Previously existing
entries in self are not removed, the new ones are added to the end of the
catalog.
write($)
Writes the current catalog to the given file.
write_if_needed($$)
Like write, but if the PO or POT file already exists, the object will be
written in a temporary file which will be compared with the existing file
to check that the update is needed (this avoids to change a POT just to
update a line reference or the POT-Creation-Date field).
gettextize($$)
This function produces one translated message catalog from two catalogs, an
original and a translation. This process is described in po4a(7),
section Gettextization: how does it work?.
filter($)
This function extracts a catalog from an existing one. Only the entries having
a reference in the given file will be placed in the resulting catalog.
This function parses its argument, converts it to a Perl function definition,
eval this definition and filter the fields for which this function returns
true.
I love Perl sometimes ;)
to_utf8()
Recodes to UTF-8 the PO's msgstrs. Does nothing if the charset is not
specified in the PO file (``CHARSET'' value), or if it's already UTF-8 or
ASCII.
Functions to use a message catalog for translations
gettext($%)
Request the translation of the string given as argument in the current catalog.
The function returns the original (untranslated) string if the string was not
found.
After the string to translate, you can pass a hash of extra
arguments. Here are the valid entries:
wrap
boolean indicating whether we can consider that whitespaces in string are
not important. If yes, the function canonizes the string before looking for
a translation, and wraps the result.
wrapcol
the column at which we should wrap (default: 76).
stats_get()
Returns statistics about the hit ratio of gettext since the last time that
stats_clear() was called. Please note that it's not the same
statistics than the one printed by msgfmt --statistic. Here, it's statistics
about recent usage of the PO file, while msgfmt reports the status of the
file. Example of use:
[some use of the PO file to translate stuff]
($percent,$hit,$queries) = $pofile->stats_get();
print "So far, we found translations for $percent\% ($hit of $queries) of strings.\n";
stats_clear()
Clears the statistics about gettext hits.
Functions to build a message catalog
push(%)
Push a new entry at the end of the current catalog. The arguments should
form a hash table. The valid keys are:
msgid
the string in original language.
msgstr
the translation.
reference
an indication of where this string was found. Example: file.c:46 (meaning
in 'file.c' at line 46). It can be a space-separated list in case of
multiple occurrences.
comment
a comment added here manually (by the translators). The format here is free.
automatic
a comment which was automatically added by the string extraction
program. See the --add-comments option of the xgettext program for
more information.
flags
space-separated list of all defined flags for this entry.
this is mostly an internal argument: it is used while gettextizing
documents. The idea here is to parse both the original and the translation
into a PO object, and merge them, using one's msgid as msgid and the
other's msgid as msgstr. To make sure that things get ok, each msgid in PO
objects are given a type, based on their structure (like ``chapt'', ``sect1'',
``p'' and so on in DocBook). If the types of strings are not the same, that
means that both files do not share the same structure, and the process
reports an error.
This information is written as automatic comment in the PO file since this
gives to translators some context about the strings to translate.
wrap
boolean indicating whether whitespaces can be mangled in cosmetic
reformattings. If true, the string is canonized before use.
This information is written to the PO file using the wrap or no-wrap flag.
wrapcol
the column at which we should wrap (default: 76).
This information is not written to the PO file.
Miscellaneous functions
count_entries()
Returns the number of entries in the catalog (without the header).
count_entries_doc()
Returns the number of entries in document. If a string appears multiple times
in the document, it will be counted multiple times
msgid($)
Returns the msgid of the given number.
msgid_doc($)
Returns the msgid with the given position in the document.
get_charset()
Returns the character set specified in the PO header. If it hasn't been
set, it will return ``CHARSET''.
set_charset($)
This sets the character set of the PO header to the value specified in its
first argument. If you never call this function (and no file with a specified
character set is read), the default value is left to ``CHARSET''. This value
doesn't change the behavior of this module, it's just used to fill that field
in the header, and to return it in get_charset().