[i18n] Confused about using plural forms

Even when using gettext the parameter needs to be passed twice:

An example for the us of this function is:

            printf (ngettext ("%d file removed", "%d files removed", n), n);

Please note that the numeric value n has to be passed to the printf function as well. It is not sufficient to pass it only to ngettext.

So we need to update our docs to match the way you are using it, or change the implementation of tr() to do that automatically. Still need to evaluate the consequences of the latter solution.

the gettext reference: http://www.gnu.org/software/libc/manual/html_node/Advanced-gettext-functions.html

I actually noticed this a few days ago, and I ended up doing what Renato did.

I'd suggest going for the more intuitive i18n.tr("%1 hour", "%1 hours", numHours), which is also similar to what the gettext API for Python does: http://docs.python.org/2/library/gettext.html

I do think that it should do the substitution automatically, what's the point in asking the user to do it?

I think the documentation might need to be fixed, but the implementation seems fine to me. For the general case, it's not possible to automatically insert the "count", as the string may have multiple format specifiers where the numeric value is not the first argument. For instance, the following example would break, if the substitution was done automatically:

tr("Folder %1 has %2 file", "Folder %1 has %2 files", count)

In this case, %1 is the name of the folder, while %2 is the count. If the implementation were to return the result of the gettext call, as a QString with .arg(count) applied to it first, the result would be incorrect.

Maybe it should be made more explicit in the documentation that the API follows the standard QString API expectations here, and does not automatically insert count or contextual values in the string result of tr() calls, but I don't think the implementation should be changed.

I changed the title of this bug, because the implementation and documentation are aligned. There is nothing in the documentation implying that the "count" argument for plural forms will be automatically replaced in a format string. It is up to the programmer to finalize formatting of their strings properly.

It works like this:

import QtQuick 2.4
import Ubuntu.Components 1.3

Text {
    text: i18n.tr("singular: %1", "plural: %1", 1).arg("1") + "<br>" +
          i18n.tr("singular: %1", "plural: %1", 2).arg(2)
}

I will update documentation.

This bug was fixed in the package ubuntu-ui-toolkit - 1.3.2060+16.10.20160814

---------------
ubuntu-ui-toolkit (1.3.2060+16.10.20160814) yakkety; urgency=medium

  [ Zoltan Balogh ]
  * Fix OptionSelectorTestCase tests.
  * Fix more OptionSelector autopilot tests

  [ Timo Jyrinki ]
  * Disable documentation building for GLES builds. Fixes LP: #1606222.
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  * Limit s390x dependencies more due to upstart/s390x problems and removed
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  [ Andrea Bernabei ]
  * ListItemLayout doc: add elide mode change example and add section about
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  * ListItemLayout doc: add explicit note about the need to bind ListItem's
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  * More Scrollbar optimizations: 20% faster creation time. Fixes LP: #1606451
  * Scrollbar: fix wrong thumb color on tap/mouse release and increase coverage
    of hover states unit tests. Fixes LP: #1608897

  [ Zsombor Egri ]
  * Fix null pointer property initializer used with 1.3 PageWrapper.
    Fixes LP: #1604780.
  * Fix BottomEdge content URL preloading. Fixes LP: #1604509.

  [Albert Astals Cid ]
  * UCUnits::resolveResource: Prefer image path if it exists. This saves
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  [ Tim Peeters ]
  * Configure colors of the buttons in the ActionBar and PageHeader through
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  * Fix assigning of constant values to a grouped property in StyleHints.
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  * Fix failing autopilot header tests.
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  [Christian Dywan ]
  * Include indexes in "offline" docs and filter out link errors.
    Fixes LP: #1603937.
  * Increase focus ring thickness from 1dp to 2dp. Fixes LP: #1602690.
  * Add a snippet about tests to the toplevel README
  * Enter/Return to trigger, Space to expand ComboButton. Fixes LP: #1523817.
  * Initialize engine variable before using it in the _engine case.
  * Use Qt.rgba instead of #0000 checking ListItem default color.
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  * Don't use a different .desktop file in the gallery tests.
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  * Update scaling docs, set QT_SCALE_FACTOR and unset GRID_UNIT_PX.
    Fixes LP: #1610208

  [ Florian Boucault ]
  * Sections: load Icons asynchronously.

 -- Zoltán Balogh <email address hidden> Sun, 14 Aug 2016 09:06:46 +0000