Do Until UserNames.EOF
Response.Write UserNames("UserName
")
RSUserNames.MoveNext
Loop
` Close the database connection
Conn.Close
%>
Scripting languages, as used by ASP, were thought of as true RAD languages, since they are 
very simple to use (e.g. no strong variable types are required). However, with the increasing 
complexity of Web applications, the usage of scripting proved to incur some serious limitations. 
Exception handling, for example, is possible in ASP, but it is very cumbersome as the following 
code excerpt demonstrates. The scalability of VB style error handling is poor, since VBScript or 
Jscript do not provide the means to process errors with throwing and catching. 
<%@ language="VBScript" %>
<%
Sub Foo()
. . .
On Error Goto ErrHandler
Set Conn = Server.CreateObject("ADODB.Connection")
. . .
` Some SQL Statements
Exit Sub
ErrHandler:
Call ErrHandler(Conn)
End Sub
Sub ErrHander(Conn)
NumberOfErrors=Conn.errors.count
for Counter = 0 to NumberOfErrors 1
Number=Conn.errors(counter).number
Description=Conn.errors(counter).description
Response.write "Error=" & Number & ", " & Description;
Next
. . .
' Also close any existing connections
End Sub
%>
Another problem with scripting languages is that an organization of the application into classes 
and libraries (namespaces) is not possible. This decreases maintainability and clarity especially 
in larger projects. Reuse of code in ASP 3.0 is difficult due to the lack of namespaces. To 
achieve reuse in ASP 3.0, functions need to be maintained in separate asp files. Then, these 
files have to be added to each page with an include directive. Another way of reuse is the 
generation of COM's, but this requires additional development time and effort. 
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