smarty template getting blank after entering js validation - smarty

Question

pinterest js
<script type="text/javascript">
(function(d){
var f = d.getElementsByTagName('SCRIPT')[0], p = d.createElement('SCRIPT');
p.type = 'text/javascript';
p.async = true;
p.src = '//assets.pinterest.com/js/pinit.js';
f.parentNode.insertBefore(p, f);
}(document));
</script>
css files
<link rel='stylesheet' href='css/fab-sales.css' media='all' type='text/css' />
<link rel='stylesheet' href='css/basic.css' media='all' type='text/css' />
codes
{if isset($products)}
<!-- Products list -->
<ul id="product_list" class="clear">
{foreach from=$products item=product name=products}
{assign var=foo value=$product.link}
<li class="ajax_block_product {if $smarty.foreach.products.first}first_item{elseif $smarty.foreach.products.last}last_item{/if} {if $smarty.foreach.products.index % 2}alternate_item{else}item{/if} clearfix">
<div class="left_block">
{if isset($comparator_max_item) && $comparator_max_item}
<p class="compare">
<input type="checkbox" class="comparator" id="comparator_item_{$product.id_product}" value="comparator_item_{$product.id_product}" {if isset($compareProducts) && in_array($product.id_product, $compareProducts)}checked="checked"{/if} />
<label for="comparator_item_{$product.id_product}">{l s='Select to compare'}</label>
</p>
{/if}
</div>
<div class="center_block">
<div align="center" id="prodList">
<div class="product">
<div class="prodImgBlock filler" style="cursor:pointer"><a href="{$foo|escape:'htmlall':'UTF-8'}" class="product_img_link" title="{$product.name|escape:'htmlall':'UTF-8'}"><img src="{$link->getImageLink($product.link_rewrite, $product.id_image, 'home_default')}" alt="{$product.legend|escape:'htmlall':'UTF-8'}" {if isset($homeSize)} width="{$homeSize.width}" height="{$homeSize.height}"{/if} />{if isset($product.new) && $product.new == 1}<span class="new">{l s='New'}</span>{/if}
</a></div>
<div class="newSocialCt">
<div class="newSocialToolBar"> <span style="left: 10px;" class="newSocialTool faveIt"> <span style="position: relative;top: 4px;display: none;" class="loader"> <img src="img/tmp/ajax-loader-white.gif"> </span></span> <span class="loaderCt newSocialTool"></span> <span class="newSocialTool pinItTool" style="float:left; margin-left:-10px; margin-right:5px;"> <img src="//assets.pinterest.com/images/pidgets/pin_it_button.png" /> </span> <span class="newSocialTool" style="float:left; width:85px; margin-left:15px;">
<div id='basic-modal'> <a href='#' class='basic'><img alt="Share" src="img/tmp/tellafriend.png" border="0" /></a> </div>
</span> <span class="newSocialTool" style="float:none; margin-right:20px;">
<div class="fb-like" data-href="$foo" data-send="false" data-layout="button_count" data-width="450" data-show-faces="true"></div>
</span> </div>
</div> </div>
</div>
<div class="productCt">
<div class="productDet" id="0"><h4>{$product.name|escape:'htmlall':'UTF-8'|truncate:35:'...'}</h4>
<p class="product_desc"><a href="{$product.link|escape:'htmlall':'UTF-8'}" title="{$product.description_short|strip_tags:'UTF-8'|truncate:360:'...'}" >{$product.description_short|strip_tags:'UTF-8'|truncate:130:'...'}</a></p>
</div>
</div></div>
<div id="push" class="clear"></div>
<div id="basic-modal-content">
<div id="tellFriendBox">
<div class="popUpHd">
<h2>Tell A Friend!</h2>
</div>
<div class="error" id="tf"></div>
<form class="" id="" method="post" action="" enctype="multipart/form-data">
<div class="eachRow">
<div>Your Name
<label style="color:#FF0000">*</label>
:</div>
<div class='field'>
<input type='text' id="name" class="required email" name="name" size='33'/>
</div>
</div>
<div class="eachRow">
<div>Friends Email Address
<label style="color:#FF0000">*</label>
:</div>
<div class='field'>
<input type='text' id="email_id" class="required email" name="email" size='33'/>
</div>
</div>
<div class="eachRow">
<div>Matter:</div>
<div class='field'>
<textarea rows='4' cols='25' id="matter" class="required" name="matter" ></textarea>
</div>
</div>
<div class="eachRow">
<div class='field'>
<input class="button" type='submit' name="tellafriend" onclick="return TellFriend(); " value="Send Mail"/>
</div>
</div>
</form>
</div>
</div>
<div style='display:none'> <img src='img/tmp/x.png' alt='' /> </div>
***after putting following javascript code for validation smarty template getting blank
<script type="text/javascript">
function TellFriend()
{
var em = /^[a-zA-Z0-9._-]+#[a-zA-Z0-9.-]+\.[a-zA-Z]{2,4}$/;
if(document.getElementById("name").value == "")
{
document.getElementById("tf").innerHTML= "* Marks Fields are Mandatory ";
document.getElementById("name").focus();
return false;
}
if(document.getElementById("email_id").value == "")
{
document.getElementById("tf").innerHTML= "* Marks Fields are Mandatory ";
document.getElementById("email_id").focus();
return false;
}
if (document.getElementById("email_id").value.search(em) == -1)
{
document.getElementById("tf").innerHTML= "Invalid Email "+"</span>";
document.getElementById("email_id").focus();
return false;
}
}
</script>
need help..and after putting $foo as URL in pinterest..pinterest count button disappering..

Answer 1

You should enclose the javascript in {literal}{/literal} tags

Answer 2

There is the great article for undestand debug process: http://blog.belvg.com/showing-php-and-sql-errors-and-debugging-a-blank-white-page-in-prestashop.html