fix example in documentation stub

docs/userGuide/userGuide.tex

@@ -236,7 +236,7 @@ execute cli::builtin::ReadFile ../examples2/automaton/DFA.txt | string::Parse @
 ./aql2 -q 'execute automaton::simplify::efficient::EpsilonRemoverIncoming <\#stdin | automaton::determinize::Determinize - | automaton::simplify::Trim - | automaton::simplify::Minimize - | automaton::simplify::Normalize - >\#stdout'
 \noindent
-echo 'a + a' | ./aql2 -q 'execute cli::builtin::ReadFile \#stdin | string::Parse regexp::RegExp \^{} - | regexp::convert::ToAutomatonGlushkov (UnboundedRegExp) -'
+echo 'a + a' | ./aql2 -q 'execute cli::builtin::ReadFile \#stdin | string::Parse @ regexp::RegExp \^{} - | regexp::convert::ToAutomatonGlushkov (UnboundedRegExp) -'
 \backmatter