include::description.adoc[]

=== Noncompliant code example

[source,text]
----
"(?:)*"      // same as the empty regex, the '*' accomplishes nothing
"(?:|x)*"    // same as the empty regex, the alternative has no effect
"(?:x|)*"    // same as 'x*', the empty alternative has no effect
"(?:x*|y*)*" // same as 'x*', the first alternative would always match, y* is never tried
"(?:x?)*"    // same as 'x*'
"(?:x?)+"    // same as 'x*'
----


=== Compliant solution

[source,text]
----
"x*"
----

ifdef::env-github,rspecator-view[]

'''
== Implementation Specification
(visible only on this page)

=== Message

Remove this part of the regex.


=== Highlighting

the part of the regex responsible of making it matching the empty String


endif::env-github,rspecator-view[]