fons/cl-mongo — pull request #6 by pnathan (2012-01-12 07:04:59+00:00)
Title: Added routine to query a document for keys.

Commit message: Added GET-KEYS on a document. This is useful in a heterogenous
collection where different documents have different keys and each may need to be queried and action dispatched separately.

I see it as similar to the function ALEXANDRIA:HASH-TABLE-KEYS.