Placeholders in language strings

Translations in language files usually look like this:

/site/languages/en.php

<?php

return [
  'code'         => 'en',
  'default'      => false,
  'direction'    => 'ltr',
  'locale'       => 'en_US',
  'name'         => 'English',
  'translations' => [
    'file.success'   => 'The file was successfully updated.',
    'file.max.error' => 'You can only upload 5 files.',
    'business.hours' => 'Our business hours are from 9 to 5.'
  ]
];

But what if you need more flexibility, if you want to add string parts dynamically, e.g. a number, a link, or the name of the file in the above example?

Placeholders to the rescue:

/site/languages/en.php

<?php

return [
  'code'         => 'en',
  'default'      => false,
  'direction'    => 'ltr',
  'locale'       => 'en_US',
  'name'         => 'English',
  'translations' => [
    'file.success'   => 'The file {filename} was successfully uploaded.',
    'file.max.error' => 'You can only upload {max} files.',
    'business.hours' => 'Our business hours are from {from} to {to}.'
  ]
];

In your code, you can now access the translation strings and replace your placeholders using the I18n::template() method like this:

echo I18n::template('file.success', null, [
    'filename' => $file->filename()
]);
// Result: "The file some-image.jpg was successfully uploaded."

$max = 3;

echo I18n::template('file.max.error', null, [
    'max' => $max
]);
// Result: "You can only upload 3 files."

$from = 8;
$to   = 20;

echo I18n::template('business.hours', null, [
    'from' => $from,
    'to'   => $to
]);

// Result: "Our business hours are from 8 to 20."