Fix # 50 - Added new rule G-4325: Never reuse labels in inner scopes.

Author: kibeha

docs/4-language-usage/4-control-structures/3-flow-control/g-4325.md

@@ -0,0 +1,42 @@
+# G-4325: Never reuse labels in inner scopes.
+
+!!! warning "Major"
+    Maintainability, Reliability, Testability
+
+## Reason
+
+Reusing labels inside the scope of another label with the same name leads to confusion, less chance of understanding the code, and could lead to bugs (for example if using `exit my_label` exits at a different nesting level than expected.)
+
+## Example (bad)
+
+``` sql
+<<my_label>>
+declare
+   co_min_value constant simple_integer := 1;
+   co_max_value constant simple_integer := 8;
+begin
+   <<my_label>>
+   for i in co_min_value..co_max_value
+   loop 
+      sys.dbms_output.put_line(i);
+   end loop;
+end;
+/
+```
+
+## Example (good)
+
+``` sql
+<<output_values>>
+declare
+   co_min_value constant simple_integer := 1;
+   co_max_value constant simple_integer := 8;
+begin
+   <<process_values>>
+   for i in co_min_value..co_max_value
+   loop 
+      sys.dbms_output.put_line(i);
+   end loop process_values;
+end output_values;
+/
+```

docs/9-appendix/appendix.md

@@ -72,6 +72,7 @@ n/a | 4260 | Avoid inverting boolean conditions with NOT. | Minor |  |  | &#1000
 n/a | 4270 | Avoid comparing boolean values to boolean literals. | Minor |  |  | ✘ |  |  |  |  | ✘
 39 | 4310 | Never use GOTO statements in your code. | Major |  |  | ✘ |  |  |  |  | ✘
 40 | 4320 | Always label your loops. | Minor |  |  | ✘ |  |  |  |  | 
+n/a | 4325 | Never reuse labels in inner scopes. | Major |  |  | ✘ |  | ✘ |  |  | ✘
 41 | 4330 | Always use a CURSOR FOR loop to process the complete cursor results unless you are using bulk operations. | Minor |  |  | ✘ |  |  |  |  | 
 42 | 4340 | Always use a NUMERIC FOR loop to process a dense array. | Minor |  |  | ✘ |  |  |  |  | 
 43 | 4350 | Always use 1 as lower and COUNT() as upper bound when looping through a dense array.  | Major |  |  |  |  | ✘ |  |  |