Question

I built some the following i18n function which is called several times when rendering view :

function e_($text)
{
    $t = Translate::Instance(); 
    vprintf($t->_($text), array_slice(func_get_args(), 1)); // outputs translated text
}

Currently, I get the instance of the Translate singleton Class inside the function.

I’ve read that dependency injection should be used instead.
But If I do use dependency injection, I will have to pass the Translate object each time into the function, right ?

This would became :

<?php e_('my text', $this->Translate);
and not simply <?php e_('my text'); ?>

Well I’d like to avoid that.

Answer 1

The way you use the e_ function is actually using an alias. That’s fine as long as you can live with it. You don’t need to use a singleton to implement an alias:

function e_($text)
{
    return $GLOBALS['e_alias']->alias(func_get_args());
}

When setting up the view layer, set the dependency:

$GLOBALS['e_alias'] = $translate;

In application context, set the global variable $translate. This will allow you to move away from the singleton (which are liars), and you actually only need a global variable.

Additionally it allows you to test views with the e_ alias against different translation implementations.

The downside is that you need to manage a list of all these special global variables, like you need to maintain for the global functions like e_.

See as well this answer to the Getting $this inside function question.