It's a package/class specification that can be used by the fields pragma to provide compile-time checking of properties.

See also base

By the way, I think it's mentioned in the 3rd edition of the Camel book too.

"What should it profit a man, if he should win a flame war, yet lose his cool?"

In reply to Re: Weird my Syntax by Joost
in thread Weird my Syntax by PetaMem

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