Conditional expressions

From: moshebox_at_[hidden]
Date: 2001-05-16 16:34:42

Hi

regarding format string of the Regex libray , the docs says that I 
can have a conditional output :

?1one:two

this is good if I have two expression , what if I have 3 or 4 , I 
need to do something like :

(?1one:)(?2two:)(?3three)

sadly this wont work , neither this:

(?1one)(?2two)(?3three)

But , the C++ to syntax highlighted HTML sample is making use of a 
format string with 5 different option , I could not understand why it 
works with that and with my software it wont.

I am writing a command line util that takes 3 params , filename , 
search expression and format expression.

<filename> "(expr1)|(expr2)|(expr3)" "(?1one)(?2two)(?3three)"

this wont work , can anyone help me understand why ?

thanks