Shib SP, how to implement an access control plugin

[Scott Koranda]

Hi,

On this page

https://wiki.shibboleth.net/confluence/display/SHIB2/NativeSPXMLAccessControl

I read "It's a simple, boolean-capable language provided as
an example of how to implement an access control plugin."

I would like to better understand what is invovled in
implementing an access control plugin. What is the best
approach?

Thanks,

Scott K