== Why is this an issue? include::../description.adoc[] === Noncompliant code example [source,java] ---- Pattern.compile("(?=a)b"); // Noncompliant, the same character can't be equal to 'a' and 'b' at the same time ---- === Compliant solution [source,java] ---- Pattern.compile("(?<=a)b"); Pattern.compile("a(?=b)"); ---- ifdef::env-github,rspecator-view[] ''' == Implementation Specification (visible only on this page) include::../message.adoc[] include::../highlighting.adoc[] endif::env-github,rspecator-view[]