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== 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[]

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== Implementation Specification
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endif::env-github,rspecator-view[]