"Andy Little" <andy@servocomm.freeserve.co.uk> wrote in message news:ci7vcj$4db$1@sea.gmane.org... Hmm Apologies. Scratch the above. I guess its not that relevent here. Anyways, after taking a look at the library(s)... it looks extremely impressive. Does it duplicate type_traits... maybe.. but as well as extending it, it also provides encapsulation of commonly used concepts. As a newbie to enable_if, I find this extremely interesting. For those not up to speed on enable_if. It provides effectively a way to switch on or switch off functions and classes based on their parameters. This saves an awful lot of work over specialising things for every case. In effect enable_if enables you to specialise a family of types all at one go. Once you have enable_if then you certainly need tools to work with it and from an initial view of the docs, many common but often hard to figure concepts are available here in encapsulated form. For myself I dont want to know the gory details... so long as it works. Like It.. Like it a Lot. :-) Perhaps this is even another major milestone in the development of C++ ! regards Andy Little