== Why is this an issue?

Nested ``++CASxx++``, ``++DO++``, ``++DOU++``, ``++DOW++``, ``++DOUxx++``, ``++DOWxx++``, ``++FOR++``, ``++IF++``, ``++IFxx++``, ``++MONITOR++`` and ``++SELECT++`` statements is a key ingredient for making what's known as "Spaghetti code".

Such code is hard to read, refactor and therefore maintain.

=== Noncompliant code example

With the default threshold of 3:

[source,rpg]
----
IF        A <> B
IF        B <> C
DOW       B <> A
IF        A <> D
...
ENDIF
ENDDO
ENDIF
ENDIF
----

[source,rpg]
----
if a <> b;
  if b <> c;
    dow b <> a;
      if a <> d;
        ...
      endif;
    enddo;
  endif;
endif;
----

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

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

include::../message.adoc[]

include::../parameters.adoc[]

include::../highlighting.adoc[]

'''
== Comments And Links
(visible only on this page)

include::../comments-and-links.adoc[]
endif::env-github,rspecator-view[]