Add description

rules/S6146/vb6/rule.adoc

@@ -1,44 +1,42 @@
-FIXME: add a description
-
-// If you want to factorize the description uncomment the following line and create the file.
-//include::../description.adoc[]
-
 == Why is this an issue?
 
-FIXME: remove the unused optional headers (that are commented out)
+There are several compilations options available for Visual Basic source code and ``++Option Explicit++`` defines compiler behavior for implicit variable declarations. Not specifying ``++Option Explicit++`` will allow creating a variable by it's first usage. This behavior can lead to unexpected runtime errors due to typos in variable names.
 
-//=== What is the potential impact?
 
-== How to fix it
-//== How to fix it in FRAMEWORK NAME
+``++Option Explicit++`` has to be set in individual source files.
 
-=== Code examples
 
-==== Noncompliant code example
+=== Noncompliant code example
 
 [source,vb6,diff-id=1,diff-type=noncompliant]
 ----
-FIXME
+Sub DoSomething(First As String, Second As String)
+    Parameter = Fist        ' New local variable "Fist" is created and assigned to new local variable "Parameter" instead of "First" argument.
+    DoSomething(Parameter)
+    Parametr = Second       ' "Second" argument is assigned to newly created variable "Parametr" instead of intended "Parameter".
+    DoSomething(Parameter)  ' Value of "Parameter" is always Nothing
+End Sub
+
+Sub DoSomething(Parameter As String)
+    ' ...
+End Sub
 ----
 
-==== Compliant solution
+
+=== Compliant solution
 
 [source,vb6,diff-id=1,diff-type=compliant]
 ----
-FIXME
+Option Explicit
+
+Sub DoSomething(First As String, Second As String)
+    Dim Parameter As String = First
+    DoSomething(Parameter)
+    Parameter = Second
+    DoSomething(Parameter)
+End Sub
+
+Sub DoSomething(Parameter As String)
+    ' ...
+End Sub
 ----
-
-//=== How does this work?
-
-//=== Pitfalls
-
-//=== Going the extra mile
-
-
-//== Resources
-//=== Documentation
-//=== Articles & blog posts
-//=== Conference presentations
-//=== Standards
-//=== External coding guidelines
-//=== Benchmarks