View source for Formatted fields in language translation strings/en

=== Format argument swapping ===
The format string supports argument numbering and even swapping. This is useful where two or more data items must be embedded in a string but differences in language structure means that the order of use of the data items is not the same.

For example, suppose we have the following code:

<source lang="php">
echo JText::sprintf( 'Balls in the bucket', $number, $location );
</source>

with this language translation string

<source lang="ini">
BALLS IN THE BUCKET=There are %d balls in the %s
</source>

Then if

<source lang="php">
$number = 3
$location = 'hat'
</source>

this would output “There are 3 balls in the hat”. But consider if you wanted to change the translation to

<source lang="ini">
BALLS IN THE BUCKET=The %s contains %d balls
</source>

This would now output “The 3 contains hat balls” which is clearly nonsense. Rather than change the code, you can indicate in the translation string which argument each of the placeholders refer to. Change the translation to

<source lang="ini">
BALLS IN THE BUCKET=The %2$s contains %1$d balls
</source>

and the output becomes “The hat contains 3 balls” as expected.

An added benefit of being able to number the arguments is that you can repeat the placeholders without adding more arguments in the code. For example, change the translation to

<source lang="ini">
BALLS IN THE BUCKET=The %2$s contains %1$d balls, so there are %1$d balls in the %2$s
</source>

and this will correctly output “The hat contains 3 balls, so there are 3 balls in the hat”.

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[[Category:Development]]
[[Category:Languages]]
[[Category:Language Development]]
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