$data = <<DATAFOO;
bla bla bla $globalvar
DATAFOO

print "$data\n" ;

##</code><code>##

bla bla bla 

##</code><code>##

bla bla bla $globalvar

##</code><code>##

## From perldiag:
=item Use of bare << to mean <<"" is deprecated

(D deprecated) You are now encouraged to use the explicitly
quoted form if you wish to use an empty line as the 
terminator of the here-document. 

## From perlop

    Customary  Generic        Meaning	     Interpolates
	''	 q{}	      Literal		  no
	""	qq{}	      Literal		  yes
	``	qx{}	      Command		  yes*
		qw{}	     Word list		  no
	//	 m{}	   Pattern match	  yes*
		qr{}	      Pattern		  yes*
		 s{}{}	    Substitution	  yes*
		tr{}{}	  Transliteration	  no (but see below)
        <<EOF                 here-doc            yes*

	* unless the delimiter is ''.  
 
 


##</code><code>##

$data = <<'DATAFOO';
bla bla bla $globalvar
DATAFOO

print "$data\n" ;

##</code><code>##

bla bla bla $globalvar