[Rivet] Plugin mechanism -- what do I do with the "extern" part?

[Holger Schulz]

Hi,

I wanted to try out Rivet's plug-in mechanism for analyses and I get stuck
with error messages from g++ (4.3) of that kind:

    error: ‘AnalysisBuilders’ does not name a type

I have implemented my analysis following the plug-in example on the wiki
page, except that I use a header file as well -- and this is where I get 
stuck.
Do I have to declare the extern "magic" in the header file as well?

Holger