how to echo in PHP like this

Question

how to echo in PHP like this...

index.php

$themeData = array();
$themeData['test_in_other_page'] = 'work';

mypage.php

{{TEST_IN_OTHER_PAGE}}

Answer 1

Something like this:

1: get the content of mypage.php

$fileStr = file_get_contents('<path>/mypage.php');

2: replace items

foreach ($themeData as $name => $content)
{
  $fileStr = str_replace('{{'.$name.'}}',$content,$fileStr);
}

3: echo that:

echo $fileStr;

This all under the assumption I understand your question. But a templating engine would be far more flexible.