All values should be undefined:
$a = [+ $a || '' +] 
$b = [+ $b || '' +] 
$c = [+ $c || '' +] 
$d = [+ $d || '' +] 
$e = [+ $e || '' +] 
First of all assign a value:
[- $a = '(this is the value in $a)' -] 
Now we have some 'Umlaute':
[- $b = "$a 
 äöü" -]
Now lets look what we are getting from this:
[+ $a +] [+ $b +]
And now a and b together: [+ "$a$b" +]
Here we have some HTML tags within the perl code,  Ok. 
optRawInput is now: [+ $optRawInput +] 
Embperl will not delete them when optRawInput is set !
[+ $c = "
 6 + 17  * 3" +]
Here we have something which looks like a HTML tag, but does not start with
a character, Embperl does not change them!
[+ "SELECT * FROM a ORDER BY b USING <; Hi There>" +]
Embperl will not translate HMTL escapes to the right characters 
when optRawInput is set
[- $e = 2 -]
[+ $d = "$e < 6" +]
Now they should have a value
$a = [+ $a +] 
$b = [+ $b +] 
$c = [+ $c +] 
$d = [+ $d +] 
$e = [+ $e +] 
optRawInput is set now to: [+ $optRawInput = 1 +] 
optRawInput is now: [+ $optRawInput +] 
[+ $c = "
 6 + 17  * 3" +]
[- $b = "$a 
 äöü" -]
Now lets look what we are getting from this:
$a = [+ $a +] 
$b = [+ $b +] 
$c = [+ $c +] 
optRawInput is now: [+ $optRawInput +] 
optRawInput is set now to: [+ $optRawInput = 0 +] 
optRawInput is now: [+ $optRawInput +] 
[+ $c = "
 6 + 17  * 3" +]
[- $b = "$a 
 äöü" -]
Now lets look what we are getting from this:
$a = [+ $a +] 
$b = [+ $b +] 
$c = [+ $c +]