How to create an if statement without else in XQuery?

Question

I want to create an instruction ifwithout a part elsein XQuery.

For example:

<results>
   { 
   if (5 = 5) then
       <foo/>
   }
<results>

How to do it?

I also tried this:

<results>
   { 
   if (5 = 5) then
       <foo/>
   else
       return
   }
<results>

which, although compiled, does not work at work!

Answer 1

There are no ifoperators without XQuery else. Return an empty sequence instead of ()or any reasonable identification element (usually this is what you need if nothing specific is defined).

if ($foo eq "bar")
then
  42
else
  ()

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"empty return statements"

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Answer 2

:

<results>
   { 
       <foo/> [5 = 5]
   }
</results>