simple tag:
  no extra whitespace           <!--#echo $var1-->
  whitespace after open delim   <!--#	 
echo $var1-->
  whitespace before close delim <!--#echo $var1 	
-->
  whitespace after command      <!--#echo 	
$var1-->

tag pair:
  no extra whitespace             <!--#loop "loop1"--><!--#echo $var1--><!--#endloop-->
  open tag:
    whitespace after open delim   <!--# 	
loop "loop1"--><!--#echo $var1--><!--#endloop-->
    whitespace before close delim <!--#loop "loop1" 	
--><!--#echo $var1--><!--#endloop-->
    whitespace after command      <!--#loop 	
"loop1"--><!--#echo $var1--><!--#endloop-->
  close tag:
    whitespace after open delim   <!--#loop "loop1"--><!--#echo $var1--><!--# 	
endloop-->
    whitespace before close delim <!--#loop "loop1"--><!--#echo $var1--><!--#endloop 	
-->