Here is a simple one liner to repeat a string multiple times with a separator:
<?php
implode($separator, array_fill(0, $multiplier, $input));
?>
Example script:
<?php
// How I like to repeat a string using standard PHP functions
$input = 'bar';
$multiplier = 5;
$separator = ',';
print implode($separator, array_fill(0, $multiplier, $input));
print "\n";
// Say, this comes in handy with count() on an array that we want to use in an
// SQL query such as 'WHERE foo IN (...)'
$args = array('1', '2', '3');
print implode(',', array_fill(0, count($args), '?'));
print "\n";
?>
Example Output:
bar,bar,bar,bar,bar
?,?,?