PHP function not working as expected - php

Question

<?php
function getPosts($showposts,$tags, $thumb_key="thumb_300x166", $thumb_class, $thumb_width="300", $thumb_height="166") {
$temp = $wp_query;
$wp_query= null;
$wp_query = new WP_Query();
$wp_query->query('tag=$tags&showposts=$showposts');
while ($wp_query->have_posts()) {
$wp_query->the_post();
echo '<div class="entry"><div class="left">';
if ( function_exists( 'get_the_image' ) ) {
$defaults = array(
'custom_key' => array( '$thumb_key' ),
'image_class' => '$thumb_class',
'image_scan' => true,
'width' => '$thumb_width',
'height' => '$thumb_height'
);
get_the_image($defaults); // thumbnail
} // end if
echo '</div>
<div class="right">
<h3>'.the_title().'</h3>'
.the_excerpt().'</div></div>';
} // end while
}
getPosts($showposts=5,$tags="news",$thumb_class="review-thumb");
?>
I don't understand why this wordpress query function isn't working. I doesn't return/print anything at all.

Answer 1

I have never used Wordpress, but I see one problem that might be the cause of this.
Which is that if you use single quotes, such as on the following line:
$wp_query->query('tag=$tags&showposts=$showposts');
$tags and $showposts are not processed and are inserted into the string literally. If you want your string to contain the values of $tags and $showposts, use double quotes, like this:
$wp_query->query("tag=$tags&showposts=$showposts");
The same goes for the array passed to get_the_image.
edit: Additionaly, your function call looks weird. You're using syntax similar to when you're providing default values for arguments, but a regular function call will look something like this:
getPosts(5, "news", "review-thumb");