Hi, Anonymous Monk Thanks for your calm advice and code. Below is code which worked. 
$html .= $cgi->div({-id=>'container'}, 
                    $cgi->img({src=>'images/pic.png', height=>'100px',
+ width=>'150px'}),
                    
                    (
                    (($session->is_expired) || ($session->is_empty))
                    ? ($cgi->p("false"))
                    :($cgi->p("true"))                                
+                 
                    ),
                    
                    $cgi->div(
                    {-id=>'menu_bar'}, 
# rest of html

[download]

And here is code, which didn't

$html .= $cgi->div({-id=>'container'}, 
                    $cgi->img({src=>'images/pic.png', height=>'100px',
+ width=>'150px'}),                    
                    
                    (
                    (while ($num <=5)
                    {($cgi->p($num))
                    ($num++)})
                    ),
                    
                    $cgi->div(
                    {-id=>'menu_bar'},

[download]

What I did wrong in 'while' case. I went through links, provided by you. So here $html .= $cgi->div#rest of code, is one big statement and rest of part on right side are expressions.

But, could not grasped the concept and structure behind parenthesis well.

And is it possible to use other Perl blocks in this fashion.?

In reply to Re^6: CGI::Ajax No head/html tags, nowhere to insert. Returning javascript anyway. by msinfo
in thread CGI::Ajax No head/html tags, nowhere to insert. Returning javascript anyway. by msinfo

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