Template:CheckPages3

The template takes the following 3 parameters:

|1= 

previous error message

|2= 

First page

|3= 

Last page

… and checks whether the parameter "Last page" is provided while the "First page" is missing. If yes then an error message is returned. If the Error message (first parameter) already contains some text then the separator ";;" and the new message is appended. If there is no error parameter 1 is returned.

Usage:

{{CheckPages3|1=previous error|2=|3=13}}
{{CheckPages3|2=|3=13}}

… results in

Error of Pages (??-13): Last page is provided, but first page is missing. Please correct the entries.